Questions on: Strawberries

Ron Smith, Horticulturist, NDSU Extension Service


Q: I met you a few days ago at a gardening event in Hope. I have a question about strawberries. A lady called me and mentioned that she found deformed strawberries (knoblike fruits) in her garden last year. All the seeds seem to clump in a small area of the deformed fruits. Is this caused by an insect? I do not have any pictures or samples of the deformed fruits, but the lady wants to know the cause of the deformation and how to deal with it. I have a copy of publication E-299, but it does not describe the injury symptoms. Your cooperation is very much needed to solve this problem. Thank you in advance. (e-mail reference)

A: These deformed fruits are called "nubbins." They are formed from a number of sources, such as frost damage to the pistillate part of the flower, lygus bug feeding activity or the lack of bee activity because of cool, windy or wet weather during the time when pollination should be taking place.


Q: I need to restart my strawberry bed this spring. What varieties are recommended for Bismarck, N.D.? I like juicy, sweet berries. I will put a few of the extra plants into a strawberry jar. I haven't done that before. Are there any special things I need to do? Thanks for your help. (e-mail reference)

A: Refer to my publication on strawberries at http://www.ag.ndsu.edu/pubs/plantsci/hortcrop/h16w.htm. You can download and make a selection from the cultivars I've listed. Growing plants in a strawberry jar is fine, but you have to pay close attention to the amount of water you provide. You need to do that every day as warm weather sets in.


Q: I planted a strawberry garden two years ago. The plants produce strawberries, but the berries are the size of a dime. I do have creeping jenny in the garden. Is that why the strawberries are so small? I do water the plants, but don’t know what kind of fertilizer I should use. What should I do to make them bigger? Thanks. (e-mail reference)

A: Strawberries are very jealous of any competition. If you have creeping jenny, it is small wonder the strawberries are undersized. I'm afraid your only alternative is to start new in a different location or by wiping out everything, especially the creeping jenny, and then replanting next spring. Go to www.ext.nodak.edu/extpubs/plantsci/hortcrop/h16w.htm and download the publication on strawberries. Strawberries respond well to fertilization twice a year. Fertilize in early spring before flowering and right after harvest. Use a 10-10-10 fertilizer broadcast over the plants and then water in.


Q: I read something on the Web that said you shouldn't plant strawberries and raspberries together. Is this true? Is it because of verticillium wilt infection? (e-mail reference)

A: What authority did the site use for the statement? Verticillium wilt is a threat almost anywhere, so that is nothing unusual. Of course, one shouldn't plant where it was diagnosed. I have had a planting of these crops together for years without problems. The rabbits and voles are the biggest headaches, not disease!


Q: I’ve had problems with my strawberry plants for the last four years. I have used Roundup and started over. I also have powdered the plants with Sevin. Last year I noticed a lot of ants in the plants and roots. I treated the plants to kill the ants and did not eat any of the fruit because of all the chemicals I used. I also noticed an ant problem in my grass. I am very frustrated and this year the strawberries are looking terrible right from the start. I pulled a few plants and noticed ants on the roots again. Do you have any suggestions? I would appreciate any advice. (e-mail reference)

A: It is apparent that the ants like the strawberry bed, so I would suggest getting rid of the berries to deprive them of such a cozy environment. Four years is a pretty long time to expect strawberries to go without a problem or two. Usually it is lygus bugs or a virus that get to them in that period of time. It is recommended that gardeners replant strawberries after three years to avoid frustrations. If you have another place to start a new berry bed, go ahead and do so. Buy fresh plants from a commercial supplier. Then get a commercial pest control operator to get rid of these critters. It sounds like you are going to be carried away by them!


Q: We have Ozark beauty strawberry plants. We have had them for about four years. The plants are beautiful, but rarely bear fruit. Last season, the plants bore fruit twice. The berries were not very big. What could be wrong? (Kulm, N.D.)

A: Ozark Beauty is an ever-bearing cultivar of strawberry, so the plants won’t bear a lot of fruit, but it should be fairly continuous throughout the growing season. Because the plants did not bear a lot of fruit last season, it may be time to replant because the plants are more than four years old. It is generally advised that strawberry plants be replaced after four years because of low fruit production. Here is a quick, thumbnail review of good cultural practices to follow for optimal berry production. Don’t bury the crown of the plants. The plants should be planted at, or slightly above, soil level. Plant in well-drained, fertile soil that gets full sun. Remove the blossoms the first growing season to get good plant establishment. Flowers rob the plants of energy needed for good root establishment. Ever-bearers should have their runners removed until the mother plant is exhausted. Then control the number of runners produced. Keep only the most vigorous runners. Use a complete fertilizer, such as 10-10-10, when fertilizing. Straight or excess nitrogen can cause excessive vegetation growth at the expense of fruit set. Do an annual cleanup in late fall or early spring using a mower. This will remove old, possibly diseased foliage and stimulate new growth.


Q: I'm interested in planting some blueberries and strawberries. My husband and I just bought a house with a nice garden area, but I'm not a huge veggie person and thought that some fruit might be nicer. What types of blueberries and strawberries would be good to plant, when should I start planting and how do we care for the plants during winter? (Fargo, N.D.)

A: Glad to help! First, forget about the blueberries. They are not going to happen in this part of North Dakota without a lot of hard work and luck! Instead, concentrate on strawberries and raspberries, which can be grown and enjoyed in Fargo. The Smiths have been doing it for years. Go to www.ext.nodak.edu/extpubs/plantsci/hortcrop/h16w.htm or www.ext.nodak.edu/extpubs/plantsci/hortcrop/h38w.htm for information to get you started next spring.


Q: I never miss reading Hortiscope. I have noted many questions about trees in strawberry beds. I have used Poast on trees in an asparagus and rhubarb bed that is 60 years old. Poast, plus crop oil, does a good job on brome and pigeongrass. (Miller, S.D.)

A: Thank you for the information! Everyone will appreciate your sharing of this information.


Q: I have a small strawberry patch that was overtaken by grass. Other than pulling out the grass, is there an easier way of getting rid of it or do I have to face the fact that I will be on my knees for the rest of my life in the strawberry patch? (e-mail reference)

A: No, you don’t have to spend the rest of your life on your knees pulling grass out of the strawberry patch! There is a herbicide called Vantage that will keep the grassy weeds under control once you get them pulled out.


Q: We have June-bearing and everbearing strawberries. They started out fine this year, bearing large, tasty berries, but now most of the berries look like buttons. I have had this problem before. They have a knob in the center of the bottom or are otherwise misshapen. I was told that this is caused by lygus bugs, also known as the tarnished plant bug. If this is the cause, what treatment should be used on them? (Britton, S.D.)

A: Someone gave you a very good probability of the cause. It is too late now to do anything. I would suggest that early next spring you mow the foliage off the plants and collect the clippings in the mower bag. Then, as the blossoms are forming, spray with an insecticide approved for strawberries to control lygus bugs. Be sure to do it in the early morning or evening hours when the bees are not active.


Q: What chemical will control grass in our strawberry bed? (e-mail reference)

A: Garden strawberries do not have a chemical recommendation for weed control. Hoeing and hand pulling are the best suggestions. Herbicides should not be applied while the plants are blooming, when runner plants are taking root or during late summer/early fall while the fruit buds are forming. This makes applying the right herbicide at the right time a tricky proposition at best! Hence, herbicides mostly are limited to commercial growers.


Q: What can I use for fertilizer or weed control on strawberries? I planted them before the rain last week. They are very hardy looking plants that were grown here in North Dakota last year. (e-mail reference)

A: The best weed control, unless you have more than a quarter acre of strawberries, is hand weeding and mulching between rows. As to fertilizer, a broadcast of 10-10-10 at a rate of 4 to 5 pounds per 100 square feet would do the trick in the absence of a soil analysis. An application of Miracle-Gro as they are attempting to get established would be even better.


Q: My strawberry patch is being taken over by dandelions. Is there anything I can use to get rid of the dandelions, but not hurt my strawberries? (e-mail reference)

A: Sorry! Good old-fashioned digging of the entire root is the only answer now, unless you want to kill everything and start fresh.


Q: We recently purchased a property that has a large strawberry patch. I don’t know very much about strawberries, except that I like them. How do I clean the patch in the spring? Do I remove all the dead foliage? Do they need fertilizing? (e-mail reference)

A: I wish people who write and ask me cultural questions dealing with outdoor seasonal plantings would give me their location. It would help me answer the question with greater accuracy. If your berries have not started growing new foliage or even if they have, get in there and cut them back with a lawn mower set as high as possible. Collect the cut foliage in a bagger attachment. This normally is done in late fall to remove the foliage that may be carrying disease and insects from the summer season. If there are no flowers showing at this time, you probably still can do it. Here are some Web sites that will give you a good background on growing strawberries:
www.ext.nodak.edu/extnews/hortiscope/fruitveg/strwbrry.htm or
www.ext.nodak.edu/extpubs/plantsci/hortcrop/h16w.htm. If you have any more questions after reading through my two sites on strawberries, get back to me and I’ll try to help you.


Q: What can you use for the control of insects on strawberry plants and when should I use it? (Cavalier, N.D.)

A: You can use Malathion before growth begins. Use Sevin or Endosulfan after growth has started and the flower buds are just separating. Do not use insecticides during the blooming stage! Use Sevin again, if needed, 10 to 14 days past blooming. Check to be sure that the damage is not a slug problem. If you do suspect the problem is slugs, carefully apply metaldehyde to the affected area. Be careful that you don’t get the bait on the fruit.


Q: I purchased Poast to kill weeds around my strawberry plants during berry growth. I’m having a difficult time figuring out what mixture to use because the directions on the package only stress the safety precautions. I also need to purchase some dacthal W-75, but it is costly. Is there a place that isn’t so costly or is there a cheaper version? I have one more question. What is the best fencing to install around the strawberry patch to keep deer and other animals away? I was told to install the fence at an angle of 70 to 80 degrees with the top of the posts pointing away from the berry patch. This is supposed to confuse the deer. (e-mail reference)

A: There should be a label that came with the pesticide. The dealer who sold it to you could get into a lot of trouble if there was no label with it. Contact the supplier for a copy of the label or contact the manufacturer. There should be an 800 number on the package. I’m sorry, but I do not know of an inexpensive source for dacthal. You are right on the money as far as the fencing goes. Purchase a solar-powered electric fence and stagger the spacing to get the deer and the animals close to the ground. You also will find birds to be a pest. Birds will eat only half of a ripe berry.


Q: I have strawberry plants that must be moved. Is there anything I can do to help the young plants survive the trauma? (e-mail reference)

A: Dig up the plants with as much root as possible and pack them in damp sphagnum peat moss. If possible, keep the plants cool in a refrigerator crisper. Turn the soil where the planting is to go, incorporate sphagnum peat moss in the bed and make sure the area is free of rhizomatous weeds, such as Canada thistle or quackgrass. Plant and water.


Q: How will this cold weather affect newly planted strawberries? In addition, I noticed many of my fall raspberries were damaged after the temperature dropped into the 20s the other night. Will they send out more plants if the first ones froze off? Looking through my Master Gardening material, I couldn’t find anything pertaining to cold temperatures. (e-mail reference)

A: Then it is an oversight in the Master Gardening program, which I will correct this fall. Thanks for pointing it out to me. Actually, strawberry plants are tough, assuming you selected cultivars that are hardy for our region. It is the blossoms that are tender. Thank goodness the plants haven’t blossomed. If you can get some water on them or cover them during cold nights, that will help protect developing buds.


Q: I have several rows of strawberry plants, but I don’t get very many strawberries. Some of these plants are 2-years-old and some are 3-years-old. Should I cut suckers off? What kind of fertilizer would help and how often should I use it? Why do I get so few strawberries? Also, when is the best time to prune and thin out raspberries? Can I cut the tops off so the plants are shorter? It’s easier to put a net over shorter plants. (Munich, N.D.)

A: Strawberries send out runners, which you want to encourage. They should be mowed down this fall after a couple of good frosts. I would then throw some super-phosphate over the patch. Next spring, spread some 10-10-10 over the area before new growth begins. If their production doesn’t improve, dig them out and replace with a new planting. Raspberries bear on biennial canes. The canes die once they have finished bearing. The young canes coming up from the crown that are not bearing this year will bear next year. Remove the old bearing canes when they are no longer producing fruit. With the new growth, cut out the weak, spindly canes and space the remaining canes about 10- to12-inches apart. Early next spring, before new growth begins, cut the canes back to the height you want them to be and dispose of the cuttings. New growth will emerge and the plants will be a more manageable size.


Q: My lawn has large patches of strawberries and clover. Broad-leaf weed treatments have not been effective. I could use a vegetation killer and reseed, but what about the strawberry-clover-grass combo areas? (e-mail reference)

A: I am willing to bet that what you are calling strawberries is actually a weed that looks like it. Potentilla bears yellow flowers while strawberries have white flowers. Strawberry plants are very susceptible to broadleaf herbicides. If you haven’t, give TRIMEC a try. It is a three-way compound that is very effective in controlling just about any broadleaf. If that fails, then the plants have built up resistance to the active ingredients or it wasn’t properly applied. You would then have to resort to a total herbicide such as Roundup.


Q: I planted a small crop of strawberry plants this year and was thrilled to see new little berries forming. My 3-year-old son has been eagerly watching them as well and was disappointed when one day we had many nice berries that were beginning to ripen and the next day they were all gone! Do you have any idea what kind of critters would be feasting on them (we used an organic spray to deter deer and rabbits) and if so, what might we use to keep them away? (e-mail reference)

A: Rabbits and birds are the big culprits along with field mice and squirrels - take your pick - there is no honor among thieves when it comes to snatching fresh strawberries! My wife has resorted to surrounding the two patches we have with chicken wire to keep critters away. The wire also covers the tops of the berries.


Q: My son just planted several thousand strawberry plants. The temperature is supposed to get down to 26 degrees tonight. Will they be okay or are they in danger? (Pembina County, N.D.)

A: Usually they are, as long as they are not in flower at the time.


Q: I had a problem with my second year tristar strawberry plants this season. The leaves turned a pale or yellowish green and the veins in the leaves remained a much darker green. This condition occurred on many of the second-year plants. It also began to appear on first-year plants late in the season. I am certain that it was not a nitrogen deficiency. I called the county extension agent and he suggested that it could be an iron deficiency. I applied an iron supplement about mid July and that helped some plants but most continued to deteriorate. Some plants reached an advanced stage where the edges of the leaves turned brown and eventually died. The condition occurred to a much lesser extent in 2001 and 2002. They are irrigated using an overhead sprinkler system. (Bismarck, N.D.)

A: Strawberries should really be watered using a drip irrigation system. The problem could be a root rot disease caused by overhead irrigation. Take your pick: phytophthora, pythium, or rhizoctinia. The exact one can only be determined by a lab test. Send a sample to the Plant Diagnostic Lab, NDSU, Fargo, 58105. Send it to the attention of Cheryl Biller, diagnostician. Do not send the sample wrapped in a wet towel. Dry the plant and send it in a zip lock bag.


Q: Our strawberry plants look healthy, had lots of blooms, but provided very little fruit. Could they be planted too thick? What kind of soil do strawberries need? (E-mail reference, Amour, N.D.)

A: Poor fruit set could be the result of lygus bugs feeding on the blooms, late frost damaging the blooms or too much rain and cool weather during the critical pollinating period. Strawberries do best in well drained soil. Use a sandy loam enriched with peat moss or well rotted compost.


Q: Last year I started a strawberry bed that grew beautifully. I pinched off the blossoms to encourage bigger fruit for this year and even snipped off the runners in the fall to encourage the parent plant to grow larger. This year the plants came back but they just aren't growing. They did start to blossom but the plants just don’t seem to be doing anything. Some have died and turned black. I gave them a shot of Miracle-Gro and a fungicide to discourage root rot. I don't know what else to do. (Tioga, N.D.)

A: Flower removal last year was a good idea but I have never heard of removing the runner plants. I suspect that you got some cultivar that is not well-adapted to your area. You have done all you can so just be patient and see what happens this year and next. Allow the plants to runner normally this summer.


Q: I have previously been using Dacthal as a pre-emergent chemical for weed control in new and old strawberry plantings. I have recently learned that Dacthal is no longer available. Is there an alternative chemical that can be used? (Bismarck, N.D.)

A: The only other pre-emergent available on the market for strawberries is Devrinol..


Q: I have several books that have pages on strawberries but none tell me what to do with last year’s growth. The strawberries were planted last year and the foliage is still attached. Should I pull it off, rake it, mow it off or leave it on to protect the crowns? When is the best time to remove the old foliage? Should you use the berries from the plant the first year? Should I fertilize the plants? Should you mulch strawberry plants over the winter or can they survive without being mulched? (Armour, S.D.)

A: You’ve asked enough questions on strawberries to develop a course on the subject! Obviously at this time of year - midwinter - you do nothing to the foliage of the berries. Typically I mow the foliage back in the fall before freeze-up or snow cover sets in. The first year flowers should be removed to keep berries from being set. That allows more energy to go into root and aerial plant development. On small patches this is not a problem, although I know many people do not follow this suggestion as they are too anxious to get the fresh fruit. Fertilization is recommended with a garden type fertilizer, such as 5-10-10 or something similar, just as new growth is beginning. Mulching is a personal choice. I have never mulched them in Fargo, nor years ago when I had a small farm in upstate N.Y. Many people will mulch them with clean straw or with a geotextile fiber known as Remay. If you are growing berries for the money, then I would suggest mulching. If you’re growing strawberries for your own consumption and yield isn't important, then you may choose not to, as long as your area gets dependable snow cover.


Q: I was given a strawberry pot with holes in the sides that contain strawberry plants. I am wondering how to care for it in the fall and winter. I would hate to lose the plants for next year. (Harvey, N.D.)

A: In North Dakota, unless you heavily mulch the pot with straw, leaves or other forms of insulation, you will lose the plants. You might find it more useful to treat the plants as annuals, replacing them each year. I have known "peat moss jackets" to work quite well at getting container plants through the winter. A plastic bag is filled with peat and the container simply plunged into it, covering the tip as well.


Q: I am doing everything wrong with my strawberries and they won't quit bearing. I bought 25 Everbearing plants from Guerneys more than 15 years ago and planted them in two rows that were 6 feet apart. The patch is now at least 25 feet long and about 13 feet wide--solid. Right now I have nine gallons in the freezer from this year alone. I don't do anything special to keep them growing, no fertilizer or anything.

I also have a coleus in my house that is 20 years, alive and very healthy. I don't enjoy gardening, but I have trouble killing a plant if I don't like it, except to throw it away. I also planted six pansy plants in June, and I now have a solid bed of them. (Regent, N.D., e-mail)

A: Congratulations on having a green thumb, good luck, good location, and a perfect environment for growing that particular cultivar of strawberry! If you were closer, I would raid your patch!

You have a coleus that is 20 years old? Send that in to the Guinness Book of Records--it simply has to be a record. Most people are happy to get them to last one growing season. You must have an amazing ability that you don't recognize in handling plants to get them to last that long.


Q: Can you tell me what is wrong with the enclosed rose bush and strawberry leaves? The strawberry leaves are from a new patch that started out good, but during the summer some of the plants started turning yellow. Is this a condition of the soil or disease? What can I do to remedy it? (Bowdon, N.D.)

A: Both plants are showing an extremely bad case of iron chlorosis, most likely induced by high soil pH. There is a good chance this can be corrected with the application of chelated iron on a regular basis. I suggest making the initial application just before new growth emerges next spring. After that, monthly applications should keep the problem from showing up again.


Q: Last year we planted 50 Redcoat strawberry plants in our home garden. Last summer a few leaves began turning yellowish green with streaks of yellow in them. Much more of the same this year on the mother plants and runners. We did harvest a nice crop of berries. A local gardener mentioned possible iron deficiency in this area. If this is the case, how do I correct it? Also, where do I send a leaf sample for a more exact diagnosis? In the ‘80s we had a 2-acre U-Pick strawberry business near Jamestown. At this time of the year we fertilized with 10-10-10 fertilizer. That particular ratio seems hard to come by in small quantities. What else could we use? ( Gilby, N.D.)

A: If the new growth had a general, over-all yellowing with the veins remaining green, it could be iron shortage. If the yellowing is streaked, it could be a virus-type pathogen. If the yellowing is overall, especially with the older leaves, and the new growth green but limited and undersized, it could be nitrogen shortage. Send a sample to the Plant Diagnostic Center, Waldron Hall, NDSU, Fargo, 58105 for a more accurate analysis. There will be a nominal charge depending on what tests have to be run. If you cannot find 10-10-10, look for 12-12-12, or anything where the analysis is the same for each of the nutrients. The only difference is the amount applied with the higher formulations.


Q: My strawberries are getting mushy and decaying on the plant. Any ideas on the cause. (Jamestown, N.D.)

A: Didn't pick them soon enough! Check the patch daily and pick those that are just ripe, not two days later or they will turn to mush. It could also be that they have been kept too wet.


Q: Can you provide me with some reasons strawberries don't set fruit? The bed was planted last summer, bloomed and set no fruit last year. This year there was a heavy blossom load but no berries. (Jamestown, N.D.)

A: Many reasons: rain at the time the pollen was ripe, cold temperatures at the same time, windy conditions at the same time so pollinators couldn't get to the blossoms, frost killing the pistillate (female) part of the flower or lygus bugs feeding on the pistillate part of the flower.


Q: I have a bed of strawberries, mostly June bearing. The edge of the bed is railroad ties. I have had problems keeping the clover and grass out of it. It seems that as soon as I get it cleaned out it starts all over again! I was wondering if there is any weed killer that would work on the clover and not on the berries, or if there is any other idea that you have. ( Woonsocket, S.D.)

A: Clover doesn't like Dicamba, which is contained in Trimec. CAREFULLY take an artist’s paint brush and dip it into a solution containing Trimec in proper concentration and "paint" the clover leaves with it. You may also follow the same procedure with Roundup, which is also effective on grass and is not soil active. I have nothing else to suggest unless you want to begin all over again.


Q: I see in your column that Poast is registered for quackgrass in strawberries. Will it also kill dandelions and other weeds without hurting the strawberries? (E-mail reference)

A: No, Poast or Vantage is a grass herbicide only. Broadleaf weeds are another problem altogether.


Q: I have a large strawberry patch. Unfortunately, the quackgrass has overtaken a portion of it. I would like to rid the area of the pesky grass but found it to be extremely time consuming to dig up each plant and pick the grass out of it. Is there anything that I can do to rid the patch of the grass that would be less time consuming? Also, any suggestions on how to rid my garden of very hungry squirrels? (E-mail reference)

A: Poast (sethoxydim), Fusilade (fluazifop-P-butyl) and Prism (clethodim) are the herbicides for grass control in strawberries, and only Poast is labeled for strawberries that are bearing. Be sure to follow label directions to get effective control. Squirrels are tough little customers to control in a garden. Exclusion fencing in the form of rabbit wire, "caged" over the plants of choice for the squirrel seems to work best for us. Also, it helps if you have a feeding station away from the garden for them to "discover."


Q: I would like to know if there is a herbicide I could put on my strawberries. It is mostly quackgrass with a few other weeds. (Berlin, N.D.)

A: Yes. Poast is registered for quack in strawberries. Be sure to follow label directions.


Q: I need to know what kind of manure is best to use as fertilizer for a strawberry garden. Also, would marigolds and/or Hoya Carnosa help keep harmful bugs away from my strawberries? (e-mail)

A: The best manure is rabbit. It is clean, easy to handle and, of course, rich in nutrients.

The lygus bug is the big pest with strawberries. It damages the flowers and causes "nubbins" to develop. I doubt the flowers you mentioned would be effective in keeping these and other destructive insects away.


Q: I have a 2-year-old bed of Tristar June-bearing strawberries. Last year they produced a lot of blossoms, but the berries never got bigger than peas and had hard centers. The garden spot is only 2 years old, and there have not been any strawberries in this area for three years. The plants are all healthy, show no signs of stress and produced a lot of runners for this year . I applied nitrogen to the plants in April of last year; they had good moisture and are in the full sun for six to eight hours daily. They are planted in a area 10 feet by 10 feet. (Selby, S.D., e-mail)

A: It sounds like the lygus bug may have discovered your strawberry patch, or you had a late spring frost that killed the pistillate part of the flower. I would tend to believe the latter, rather than the insect problem that quickly.

Generally, these critters become a problem after about three years. But, the lygus bug could be "housed" in other crops or weeds adjacent to your strawberry bed. I would suggest a good examination of the plantings to check for the lygus bug. They are small but can be easily monitored with sticky white cards placed throughout the berry patch. I also suggest cleaning up any garden or leaf litter in the immediate area and getting rid of weeds in the area, as the bugs can overwinter in such material.

Another possibility is the existence of too much rainy weather at the time the pollen was mature, causing poor fruit set.

To protect against a spring frost, cover the patch with Remay, a geotextile material that provides protection down to about 28 F yet allows the plants to breathe when the sun comes out the following morning.


Q: I am doing everything wrong with my strawberries and they won't quit bearing. I bought 25 Everbearing plants from Guerneys more than 15 years ago and planted them in two rows that were 6 feet apart. The patch is now at least 25 feet long and about 13 feet wide--solid. Right now I have nine gallons in the freezer from this year alone. I don't do anything special to keep them growing, no fertilizer or anything.

I also have a coleus in my house that is 20 years, alive and very healthy. I don't enjoy gardening, but I have trouble killing a plant if I don't like it, except to throw it away. I also planted six pansy plants in June, and I now have a solid bed of them. (Regent, N.D., e-mail)

A: Congratulations on having a green thumb, good luck, good location, and a perfect environment for growing that particular cultivar of strawberry! If you were closer, I would raid your patch!

You have a coleus that is 20 years old? Send that in to the Guinness Book of Records--it simply has to be a record. Most people are happy to get them to last one growing season. You must have an amazing ability that you don't recognize in handling plants to get them to last that long.


Q: Previously I wrote to you and you diagnosed my strawberries as having angular leaf spot. We tilled some of our plants under before we realized that it is carried over in the soil. What can I plant in this spot now that won't contract this disease? I've been thinking about asparagus, but I'm not sure. (New Salem, N.D.)

A: Asparagus and/or rhubarb sounds like a winner to me! These two are fairly tough and dependable. 


Q: We have a fairly large patch of strawberries, but have been getting few berries out of this patch. What type of fertilizer should we be using and how often? Also, what should we use for weed control? We also have a large patch of raspberries along the south side of our garage and we've always gotten quite a lot from them except this year. Is it possible that this patch is dying out? It is more than 10 years old and, we have never done anything with it except to cut out the dead canes. (Barnesville, Minn.)

A: Your strawberries may very likely have a virus disease, one of the symptoms of which is a yield reduction. They and the raspberries should be fertilized twice a year; once in the spring at initial growth or green-up, and again right after harvest. The material to use is 5-10-5 at about 10 to 15 pounds per 100 square feet.

Raspberries just don't "die out" unless something is killing them. It be virus, root rot, cane cankers, anthracnose, cane borers etc.

Both crops require constant attention to good management practices to be sustained productively. For example, the old mother strawberry plant should be tilled up each year, allowing the daughter plants to be more productive. The following year, those daughters are tilled and so forth.


Q: How and when do I plant tulip seeds? Also, what do I spray my flower and strawberry beds with to control weeds? When do I transplant fruit trees that are only 3 feet tall now? (Roscoe, S.D.)

A: Tulip seeds can be planted in mid-September. There are a number of herbicides that can be used in flower beds and strawberry plantings. If the herbicide is registered for a particular crop, it can be used on that crop and the crop consumed, providing the label instructions are followed.

Transplanting of young fruit trees can take place this fall, after they have dropped all their leaves. At that point they are considered dormant. Fall planting allows for the root system to get re-established before the winter closes in. The trees will take off much better the following spring.


Q: I fertilized my strawberries right away this spring, but when I should fertilize again? (New England, N.D.)

A: It is a good idea to give your berry crops a couple of fertilizations per year--in the spring before fruit set and again after harvest. That way, the crops are at their optimum for setting and developing fruit and for building tissue and carbohydrates for next year.


Q: My question for you is how can grass/weeds be kept out of strawberries (without physically pulling)? Is there something that can be sprinkled/sprayed on without damaging the strawberries? If so, what is it and where can I buy it? (Pukwana, S.D., e-mail)

A: The materials that are cleared for strawberries are as follows: Dacthal, Devrinol, Forumla 40, Poast and Prisim.


Q: For the first two or three years my Tristar strawberries did very well, bearing fruit from spring until fall. For the past couple of years, they have blossomed and the fruit appears, but withers before maturing. The plants have also thinned out a lot. The local nursery told me to use Bonide Mite and Insect Spray with Kelthane. After reading the cautions on the bottle I'm hesitant to use it. What do you advise? (Moorhead, Minn., e-mail)

A: These day-neutral strawberry plants lose their productivity capacity after about a year, if they should survive our winter at all. Be happy you got what you did with them! We normally recommend that growers should not expect any more than a single season from the day-neutrals, and encourage them to plant some June-bearing cultivars like Honeoye, Redchief, and Gloosecap.

So spray no more, it won't do any good. Simply replace them with something more productive.


Q: Last year half of my strawberries had a hard end on them. I've been told that an insect is causing this and that I should spray them before the berries start to form. Could you please advise me on what I should do? (Waubun, Minn.)

A: Nubbins, the bane of strawberry growers! They could be caused by an insect, known as the lygus bug, or they could be caused by a late frost when the blossoms were at their most vulnerable, fully open state.

Most strawberry plantings after three years do have some insect problems, so it is a good idea to spray with Sevin just prior to blossom opening.

You might also keep a sharp lookout for late "pocket frosts" that can selectively damage some of your blooms. If frosty conditions are predicted, you would need to provide an overnight covering with a geotextile material in the lowest areas, or those at the base of a slope. Geotextile material allows air and water movement. 


Q: I ordered some strawberry plants and this other plant came up with them when I planted them. It got real tall with little yellow flowers. Can you tell me what they are? (Eureka, S.D.)

A: Your mystery plant was a weed known as velvetleafsomething you don't want to encourage! So keep any future volunteers rogued out before they flower and set seed.


Q: Could you send me some information about strawberries, juneberries and raspberries for northern Minnesota? (Newfolden, Minn.)

A: Refer to the following publications from the NDSU Extension Service: "Strawberries" (H16), "Refreshing Raspberries for Home-Grown Goodness" (H38) and "Juneberry" (H938). If you require anything further, please get back in touch!


Q: I have been trying for three years to get strawberries started. My problem is they won't make any runners. They just grow in clumps. I have some berries but most are small. I have been adding all the grass and leaves in the form of compost for about 15 years and some 5-15-5 fertilizer for about the last five years. The other garden plants do well.

I have heard of others who had a similar problem and a spray of some kind seemed to be the answer for them. What is the product to use? (Garrison, N.D.)

A: I have not heard of strawberries not runnering before. It must be the nutrient status, especially the nitrogen, is too low. I would suggest obtaining some Miracle-Gro ( a water-soluble powder) and spraying it on your strawberries this spring. This does a beautiful job of stimulating my strawberries to runner quite heavily.


Q: Can you tell me what the ratio of Poast is that I should spray on my strawberry patch to get rid of the grass? My bed has an area of 200 square feet. I also would like to know the application times and any other info that would improve my situation without having to dig up my patch. (e-mail)

A: Someday universities will turn out doctorates in pesticide label reading and interpretation! The Poast label just about needs one. Based on what I was able to glean, I have come up with the following for your application rates:

Maximum application for the season per acre is 2.5 pints. Your 200 square foot patch is just 4.4 percent of an acre; therefore, you would apply 4.4 percent of those 2.5 pints to your 200 square feet. This equals about 52 milliliter or 1.8 fluid ounces of Poast being applied to that area. You need a minimum of seven days between application and harvest.

The lesser of the two evils may be to simply dig up the patch, kill off everything else with Roundup, and replant. Hope this helps!


Q: I have an established strawberry bed thick with grass. Last year I used Poast twice in the spring while the grass was still young and once in the fall, but no improvement. Is there a suggested concentration for strawberries? My plot is approximately 200 square feet (e-mail)

A: If you have used Poast based on label rate, it should have taken care of the grass in your berries. If it didn't, then you either have tough grass, or timing, application technique or something else was not right. You might be better off digging up a small patch of strawberries early next spring and killing everything else off that comes up after that with Roundup. Then replant.


Q: What is best to put on strawberry plants for winter, and how should I care for my asparagus? Is it OK to put orange and grapefruit peeling in the garden? Is it OK to till poplar leaves into the garden? (Gackle, N.D.)

A: Either put up a snow fence around your strawberries, or cover them with clean straw, right after freeze-up but before serious snow falls.

Allow the tops of your asparagus to remain. They will influence snow collection, which will provide critical moisture next spring.

I'm assuming that you are composting your peelings first— if so, then OK. If not, then no.

You can till the poplar leaves into your garden soil. Just don't overdo it, or you will tie up nitrogen next year.


Q: Can you tell me what will kill the weeds in my strawberry patch? Also, my apricot tree was full of blossoms, but the apricots got 1 inches in size and they soon disappeared. Why? Can you also identify the enclosed sample of a weed that is taking over my garden? (Erie, N.D.)

A: Review information on weed control in strawberries contained in "Strawberries" (H-16), a publication of the NDSU Extension Service. Be sure to use the correct type of herbicide at the right label rate. Basically, Dacthal will control germinating weeds, while Poast is used for grass control. The only guess I can come up with is that squirrels thought they had a priority right to your apricots. I'm sorry, the weed sample had rotted beyond any possible recognition by the time it got to me. Please try again, but pack it dry, rather than moist. Thank you!


Q: Can you tell me how to winter my strawberry pot? What temperature should I allow it to get down to, and should I clip off the plants before putting it away? (e-mail)

A: I would suggest keeping the pot outdoors if possible. I am afraid of temperature shifts that could tease the plants out of dormancy too early. Here is my suggestion: dig a hole, plunge the pot into it and mulch heavily after the ground initially freezes in October. If this is not possible, get some bales of straw and stack them around the pot. Take another two bales and break them up and scatter them over the pot as well, and cover with a tarp to keep in place after the initial freeze-up.

While you don't want them going into winter dry, you don't want them to be too wet either, or your pot may be damaged. Remember that when water freezes it expands 9 percent, or increases its volume by 11 percent, so the trick is to get the soil frosted, but not frozen hard.

Quite frankly, I have never done this, so this is not advice from experience, just simple logic. If any of our readers have a better suggestion, I'll pass it on to you!


Q: Can you tell me what is wrong with my tree? I think it is a cottonwood. I also would like to know why my Larime strawberries are not bearing fruit? (Binford, N.D.)

A: Poplars or cottonwoods are prone to a plethora of diseases. In your case, the problem is Septoria leaf spot, a fungus brought on by rainsplash, humid weather, and poor air circulation.

Best control is sanitation—removal of all fallen leaves this autumn. You may want to try a fungicide next spring after the leaves open to protect the tree. Something like Daconil, Maneb, or Mancozeb would be good selections.

Your Larime strawberries should have set fruit by now. Perhaps you've fertilized too much or the soil is too high in nutrients. If they don't fruit next year, replace them (assuming you want the fruit and not the ground cover)!


Q: Please tell me what kind of a plant this is? Would you please recommend a variety of strawberries? (Regan, N.D.)

A: The plant sample you sent in was velvet leaf Abutileu theophresti. This is an annual that you want to keep from setting seed.

This past spring was not exactly condusive to growing good strawberries—wet and cool—remember? You may want to try one of the June bearing varieties from the enclosed publication, "Strawberries" (H16), available from the NDSU Extension Service. It lists several. Two of my favorites are Honeoye and Glooscap.


Q: We enclosed our strawberry plants with green-treated landscape timbers, and remember reading something in your column about how arsenic leaches from the timbers. Are the strawberries still safe to eat? (Grenville, S.D.)

A: The amount of arsenic reaching the strawberries would be essentially nothing. They should be perfectly safe to eat. 


Q: I would like to know what I can spray on my strawberry plants, rhubarb, and iris bed to help control quack grass. I can't move it to another location because it is everywhere. Once I read an article you wrote about Poast or something like it. (Monsfield, S.D.)

A: You remembered correctly—it is Poast (sethoxydim). You apply it to actively growing grasses, but you cannot apply it within 7 days of harvest. For other information, refer to the label.


Q. I am interested in some varieties of strawberries for this area that can tolerate our growing conditions. What do you suggest? (Minot, N.D.)

A. There are a number of strawberries that can successfully be grown in North Dakota, such as Honeoye, Gloosecap and Redcoat. NDSU Extension Service publication H-16, "Strawberries," is enclosed for further information. Others may obtain this publication from any county office of the NDSU Extension Service, or by calling the Ag Communication Distribution Center at NDSU, (701) 231-7882.


Q. I started some strawberries a few years ago and didn't take care of them like I should have. Now they are thick. Can they be dug up and transplanted? What is the best time of  year to do this and should chemicals be used? Thank you. (Platte, S.D.)

A. Early spring is the best time to transplant. Refer to the enclosed circular, H-16, "Strawberries," for details. Others may obtain a copy of this publication at their local county extension office or by contacting the NDSU Extension Distribution Center, Box 5655, Morrill 10, NDSU, Fargo, ND 58105-5655.


Q. How is one supposed to water plants with Miracle-Gro; spray type or root way?

My strawberries were winter hurt two years ago. They didn't do anything last year, and by the looks they will not do much this year. Should I dig them all up and get a new set, or is there something I can do to bring them back to bearing again?

Thank you for all the good information you supply in the paper. (Linton, N.D.)

A. Miracle-Gro is applied as a liquid spray over the foliage where it is rapidly absorbed by the plant.

It appears to have been a bad year for strawberries--thanks to our long, tough winter. At this point, I would suggest starting over (see circular H-16, "Strawberries") to get something productive that is worth picking.


Q: What do you recommend for fertilizing strawberries? (Forman, N.D., e-mail)

A: Strawberries need fertilization right after harvest, or before the onset of flower-bud formation that takes place in August. About 5 pounds of 10-10-10, or something close to that, per 100 square feet of row. If the plants show a nitrogen deficiency, then perhaps a shot of some SCU (33-0-0) at about 1 pound per 100 square feet of row would green them back up again.


Q: I was just wondering if it is to early to plant strawberries, in Lisbon, N.D.? (Lisbon, N.D., e-mail)

A: I would suggest waiting until we are into a more settled weather pattern. I hate to give dates because the weather in spring is so fickle, but I would guess between May 1 and Mother's Day (May 14) should be OK.


Q: Is there something we can apply that would kill the weeds in our strawberry patch but not harm the plants? (Esmond, N.D., e-mail)

A: There are several: Dacthal W-75, Devrinol 10-G, and E-2, Formula 40, Poast, Princep, and Prism.


Q: What can be used to control sowthistle and wild morning glory in my strawberry and raspberry beds? (e-mail)

A: Two tough ones! You could try to spray Roundup carefully on them, trying not to get the spray on the strawberry foliage. Since it is not soil active, it would not hurt the adjacent strawberry plants. There is nothing else I can come up with that you could use in a broadcast manner. Sorry!


Q: I have a very nice strawberry patch with lots of green plants and many blossoms, but no strawberries. Could you tell me what the problem could be? (Stockholm, S.D.)

A: Could be one of two things: one, a late frost when the blossoms were open and vulnerable, or two, the lygus bug feeding on the pistillate (female part) of the flower.


Q: I have two questions for you. What do you recommend for western North Dakota for everbearing and Junebearing strawberries? Can you use any chemical weed control in strawberries? Also, will liquid bleach mixed with water hurt garden plants and the soil? A lady is putting it in her Miracle Gro applicator attached to a garden hose and spraying her plants so her puppy doesn't use them for a bathroom. She was wondering if this would hurt the plants and soil. (E-mail reference, Stanley, N.D.)

A: Good grief! Bleach in her Miracle-Gro? I don't believe it! If she hasn't killed everything yet, she is simply lucky!! I advise against it! This sounds like something that comes out of the mouth of the Jerry Baker organization, America's so-called "Master Gardener." The strawberries that you would grow in western North Dakota wouldn't be any different than what can be grown in the rest of the state. Redcoat, Honeoye, and Glooscap seem to work best with the growers I have communicated with.


Q: I was wondering, what is the best time to move some rhubarb plants, strawberry plants and mums? (E-mail reference, Morris, M.N.)

A: The best time is: rhubarb, early spring; strawberry plants, spring; mums, in the fall.


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