Thursday, December 20, 2007
Several factors could be affecting cucumbers
John Arbogast
Landscape consultant John Arbogast answers your questions every Thursday. Send questions about your lawn, garden, plants, or insects to:
Dear John
5102 Greenfield St. SW
Roanoke, Va. 24018
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Q: I’m getting an early start on my New Year’s resolutions. I need your help with a resolution I've made to have a good crop of cucumbers for the first time in years. The soil in my small vegetable garden looks great thanks to my work over the years adding organic matter and growing winter cover crops. However, I’ve been unable to grow cucumbers that survive for more than about eight weeks. Cucumbers are my main crop in this garden. I’ve tried different cucumber varieties with resistance to just about every disease, including bacterial wilt. I have seen very few, if any pests on the cucumber vines. What could be the problem?
A: There are several potential causes for this problem that could be happening alone or in combinations. I, too, have had problems growing cucumbers.
How much moisture do your young plants get? Even though the organic matter you’ve mixed into the soil has worked to retain water plus your improved soil quality has made it easier for strong cucumber roots to grow, early vine death happens if young cucs cannot take in ample moisture. Unfortunately, the opposite is a problem. Cucumber vines will die due to the reduction of air in the soil if that soil is continually wet. This last situation will result in our clay-based soil of western Virginia if cucumbers are watered each day or if the organic mulch around them is deeper than 2 inches.
Have you tested the soil pH? Cucumbers become weak if even a good quality soil has acidity below 6.0 pH or alkalinity with pH above 7.0.
Common cucumbers need the help of busy bees to take pollen from male flower parts to female flowers in order for fruits to be produced. If you don’t recall seeing many bees in your small garden area, do what I’ve done in luring bees to the garden area. I’ve grown catnip in scattered garden spots, since bees love the flowers more than cats love the leaves. I’ve also grown bright-colored flowers near my cucumbers.
Inadequate sun of less than eight hours of direct sun per day will limit cucumber vigor and flower production. Recall now the path followed by the summer sun and discover trees that might need pruning or structures that can’t be moved but indicate the need of moving the cucumber patch.
What about fertilizing? It is true that garden soils with a lot of organic matter require smaller amounts of nutrients, but remember that cucumbers are considered “heavy feeders.” Generally, the soil for cucumbers should be fertilized with a balanced fertilizer such as 10-10-10 just prior to planting plus two surface applications at the base of vines during the growing season.
Q: I recently purchased a home with 18 blueberry bushes that are not in a sunny spot. I would like to relocate them if possible. Can these established bushes be successfully transplanted? If so, can this be done now in the winter? How can I proceed (i.e., when would be the best time, fertilizer, water, etc.)?
A: Physical limitations will be the same anywhere. If the 18 blueberry bushes have gotten so big that it would be impossible to dig all their roots, then transplanting is out of the question. Success can only be expected if sufficient amounts of roots are removed with each plant.
I’ll have to answer using suggestions here in Roanoke. Soil warmth is necessary for transplant recovery of most edible as well as landscape plants. Here, it is too late for moving plants due to chilling and partial freezing of the soil.
Soil warmth plus plant dormancy or slow growth are both necessary for transplanting. Here in Roanoke, we find those two requirements in early spring and in mid fall. Think of the times when those two requirements come together in your area.
Blueberries need an acid soil pH. So, take a soil test now (if the soil is not frozen) so you can know how much if any agricultural sulfur or aluminum sulfate should be mixed into the new location to reduce pH (increase acidity) if the existing pH is above 5.8. Add soil acidifiers many weeks prior to planting to give some time for pH change to occur.
Addition of a small amount of fertilizer after transplanting to help plants through their first growing season is helpful. However, use only slow release fertilizer. You don’t want to stimulate rapid shoot growth while the roots are still recovering.
After-transplanting care is crucial. In Roanoke, water newly installed plants faithfully but only once a week during their first growing season. Our clay-based soils retain moisture. More frequent waterings cause plants to droop due to elimination of oxygen in soil, while limited or no waterings can cause plant death when the weather becomes stressfully hot.
