October 23, 2003

Hortiscope

Ronald C. Smith, Horticulturist
NDSU Extension Service

Q: I transplanted several raspberry plants two years ago to the northeast corner of my vegetable garden. They are growing well and look healthy. There were some berries this summer for the first time. They have re-seeded into a grouping and I am wondering if the plants should be in a row supported by a fence? What time of year is best to fertilize and transplant raspberries? (Brookings, S.D.)

A: The raspberries probably have suckered into a grouping rather than re-seeded. Left alone, the plantings will spread into a thicket that would require the cleverness of Brer Rabbit to get to the berries without getting all scratched up! They should be in rows and tied up or supported in some fashion. If you can send me your mailing address, I will forward information to you in greater detail.

Q: We repotted houseplants using new soil and beads that retain moisture. Our jade tree was enormous and full of fat leaves but now it is yellow and dying. It also happened to a sheffaleria. The soil doesn't dry out between waterings so it might be root rot. What do you think? (Mandan, N.D.)

A: I think you hit the nail on the head or close to it. If the roots are not rotting, then they are starved of oxygen due to the continuous saturation.

Q: I’m looking for information on the fall care of clematis. We recently moved to this location and discovered the clematis. How do I prepare it for the winter months? (Mobridge, S.D.)

A: When you say "discovered" clematis, I assume you mean that you purchased the property and found out you had one growing there. Clematis only needs a basic mulch cover on the crown after the soil freezes. Keep it moist before freeze up and it should get through the winter in good form.

Q: I grew some apple and swan gourds for the first time this year and I love them. I picked them and they have been curing for three weeks but I couldn't wait to paint some. I painted them and coated them with polyurethane. How long will they last? (E-mail reference)

A: If you drilled a small hole in the blossom end to allow for air to enter and dry them from the inside, they should last an average human life span.

Q: Can I prune blue spruce at this time of year? I have always been told to snip back new growth in the spring while the new growth is still soft. I have also heard that pruning while in the dormancy stage is good. I would like to do some this fall. Also, we have a new lawn that is two years old and am wondering if we can give it a weed treatment this fall. (Madison, S.D.)

A: Pruning should take place during early spring or late winter dormancy, not now. Do the weed treatment on your lawn if you can do it within the next week.

Q: I was eating a peach tonight and found inside the pit, a stringy, black, soft, rubbery substance. It was black and kind of mushy. Would you happen to know what this is? (E-mail reference)

A: It was probably the peach seed itself. The pit is just the outer covering of the seed. Based on your description and the time of year, the seed could have begun rotting by the time you got to it. The fact that the pit was open is an indication that the fruit was overripe.

Q: A week or so or go I noticed that one of my spruce trees had branches where the needles were turning yellow or brown. Most of the damage was on the north side of the tree, which does not get water from the lawn sprinkler. Now I see the problem developing on all the spruce trees in my yard. I assume it is drought-related and plan to start my fall deep-watering program early this year. (Jamestown, N.D.)

A: It could be spider mite damage. They go after evergreens and other shrubs when rainfall or overhead irrigation is lacking. You might try to "wash" the foliage with a blast of water this fall prior to freeze up to keep them from settling in for the winter and causing problems next year.

Q: I've been putting Miracle Gro on acid loving plants like hydrangeas, azaleas, and dogwoods. The instructions say continue into the fall, even after the leaves fall. The instructions on their rose shrub package are silent on fall feeding. Does that mean don't apply it? (Jamestown, N.D.)

A: That is simply good marketing on their part. You need only about half as much fertilizer as they state to have decent looking, healthy plants. So stop! It isn't needed now for your woody plants, including the roses.

Q: I would like to know how late this fall I can spray for dandelions and Canadian thistle and still get effective control. (Lamoure County, N.D.)

A: It’s probably too late if you’ve had a killing frost in your area. They will not respond when they have been shut down by cold weather.

Q: I have a young redbud tree that my neighbor would like to plant a seedling from. There are many smaller trees growing up around it, so I said he could have one. He says it’s okay to plant in late fall or early winter but I've always heard spring was the best time. (E-mail reference)

A: It depends on where you live and the size of the transplant. Early spring might be better, if you live in a region of extreme cold and exposure. Otherwise, fall would work because there is not as much demand on the top part of the plant and the roots would have time to get established before the ground freezes.

Q: We have a schefflera tree at my place of employment. It is tall and skinny. Our boss wants us to cut it into three different pieces and replant. Will that work, and if so, does it matter what time of year it should be done? We want it to bush out into a better plant. (E-mail reference)

A: Schefflera can be propagated by taking terminal cuttings and air layering. So what your boss wants should work, if I understand you correctly. It makes little difference as to when this is done. You might want to look into supplemental lighting after the operation is over to keep it from getting leggy. They thrive under high light intensity, excluding direct sunlight.

Q: We pruned our lilac bushes quite short last year. While the bushes have grown back, we had only one lilac branch bloom. Is there a reason why the bushes didn't bloom this year? How much should the bushes be pruned and still have blooms the next year? (E-mail reference)

A: Lilacs will not bloom the following year after a heavy pruning. Allow them to grow this fall and spring without pruning and they should flower for you next spring. When pruning is needed, it should be done as the flowers are fading and before seed can be set. Any pruning after Aug. 1 (as a generalization) will result in the reduction of flowers the following year.

Q: I received some hydrangea cuttings from my grandmother, which I would like to start growing to keep hers alive. I cut them this past Saturday and they are in a vase with water. Can I still start new growth with a peat and sand mixture? (E-mail reference)

A: They might if you take them out of the water, make a fresh cut across the base, dip them into a rooting powder and then stick them in the sand and peat mixture. The best and easiest rooting takes place if you use cuttings taken during May or June.

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: My wife bought a plum last year, which was so delicious that I saved the pit. It's been drying on a window sill for three months. Is it dry enough? Since it's almost winter, should I just let it sit on the sill until spring? Should I plant it indoors or outdoors now? Do you have any specific planting instructions such as soil type, depth or exposure? (Rosemount, Minn.)

A: Plant it outside now. The pit needs to go through the winter in order to germinate. Let's hope it does so you can enjoy a whole tree full of the plums in a few years! Plant it about four inches deep.

Do you have a gardening or houseplant question? Write to Hortiscope, Box 5051, NDSU Extension Service, Fargo, ND 58105 or e-mail to Ron Smith at ronsmith@ndsuext.nodak.edu. Note to e-mail correspondents: please identify your location (city and state) for most accurate recommendations.

###

Source: Ron Smith, (701) 231-8161, ronsmith@ndsuext.nodak.edu
Editor: Rich Mattern, (701) 231-6136, richard.mattern@ndsu.nodak.edu