Q&A: problems with blueberries and zucchinis
Garden writer Ciscoe Morris on the mummy berry fungus and on zucchinis that aren’t getting pollinated.
Special to The Seattle Times
‘Edibles for Fall and Winter’ at Swanson’s Nursery: 11 a.m. Aug. 17. Gardening author Bill Thorness (“Cool Season Gardener”) explains what to plant and how to get your fall garden growing robustly. 9701 15th Ave. N.W., Seattle; free (www.swansonsnursery.com/seminars-events).
Highline SeaTac Botanical Garden Ice Cream Social, Silent Auction and Plant Sale: Noon-3 p.m. Aug. 17. Professional garden advice, plant sale, silent auction and more. Free ice cream to the first 300 guests. Ciscoe Morris speaks at noon. 13735 24th Ave. S., SeaTac (www.highlinegarden.org).
In the Garden
Q: For years my blueberries have been highly productive. Last year and this year too, the berries are loaded on the bushes and just before starting to turn dark they suddenly wither, turn whitish, shrivel and fall to the ground.
A: Your blueberries are infected with a fungus disease known as mummy berry. In addition to the fruit problem, secondary infections often cause branch dieback as well. This is a very difficult disease to control.
The best defense is to gently (blueberries have shallow roots that can be easily harmed) rake up and dispose of the fallen shriveled berries as often as possible. The mummies sprout mushroom-like fruiting bodies that produce billions of spores that are splashed and blown to developing flowers by wind and rain.
Once all of the fallen berries have been removed, cover the area with a layer of mulch to help prevent the remaining spores from reaching the flowers. It can also help to remove any dead shoots as soon as they are noticed. Approximately three weeks after initial infection, secondary spores form on blighted flowers and shoots, which continue to spread the infection.
Fungicidal sprays have to be timed perfectly and several applications may be required in order to be an effective deterrent. Fortunately, there are varieties of blueberries that are highly resistant to the disease. If your bushes are severely infected, it might be time to replace them. “Bluetta,” “Liberty,” “Darrow” and ‘‘Olympia” should produce enough delicious, healthy crops of blueberries for you to enjoy blueberry pie a-la-mode hassle free for years to come.
Q: I used to get so many zucchinis I couldn’t eat or give them away fast enough to keep them from getting huge. This year, the foliage looks great, but the squash hardly grows; then rots on the vine. What’s going on?
A: Your zucchinis aren’t getting pollinated. We rarely faced this problem in the past.
Zucchini, as is true of all squash, produce both male and female flowers. In order to produce healthy fruit, a bee has to transfer pollen from the male flowers to the female ones. Unfortunately, due to a host of problems, there just aren’t as many bees doing the work for us as there used to be.
All plants are on Earth to reproduce; thus fruit that lacks seed will be aborted at some point, and usually with squash, it’s after they grow a few inches. One way to help remedy this problem is to integrate flowering plants known to attract the honeybees, bumblebees and native bees that are needed for pollination of squash in or around your vegetable garden.
Some annual flowers frequented by bees include sweet alyssum, aster, zinnia and verbena. A few of the many herbaceous perennials and shrubs attractive to bees include lavender, Liatris (gay feather) Stokesia (stokes aster) Echinops ritro (globe thistle), Gaillardia and the newly introduced Digiplexis.
If, after adding bee-attracting plants, there still aren’t enough pollinators around to do the job, you must be the bee. Use a small paint brush to transfer pollen from the male flowers, which lack a fruit at the base, to the stigma or uppermost part, of the female flower, which has what resembles a tiny zucchini at the bottom.
Ciscoe Morris: firstname.lastname@example.org “Gardening With Ciscoe” airs at 10 a.m. Saturdays on KING 5.
About Ciscoe Morris
Ciscoe Morris' column runs Thursdays. His show "Gardening with Ciscoe" airs at 10 a.m. on Saturdays on King 5.