Nighttime Is The Perfect Time To Hunt Garden Pests
Q. Something is eating my rhododendron and hosta leaves and various flowers in my garden. I can’t find the insect. What’s destroying my plants? Kay, Spokane
A. There are a number of munching insects that prowl at night and hide during the day - weevils, slugs and earwigs, to name a few. Don your sleuth hat, grab a flashlight and go hunting for the culprits. It’s amazing how many critters work the night shift.
Weevils leave behind pinking shear marks on the leaf edges of rhododendrons, lilacs, peonies and hosta. Slugs leave behind silver trails and ragged leaves. Earwigs munch holes in leaves and destroy blossoms as do many other munching insects.
Before spraying for these critters, find them first. Make sure they are the villains. And, be prepared to explain to the neighbors why you are prowling the garden in the dead of night, carrying a flashlight.
Q. What causes the heads of broccoli and cauliflower to open up and how can we prevent it? Susan, Spokane A. Recently we experienced a number of days that were unseasonally hot. Broccoli and cauliflower are greatly affected by high temperatures. Not only will their flower heads open, but the plant itself suffers.
Next spring, set your plants out 2-3 weeks before the last killing frost, making sure to protect them against these frosts. Keep them moist at all times; they are very sensitive to moisture stress. To protect the soil from losing water, cover the soil around the plants with a mulch of grass clipping, straw, compost, etc. Check it every so often to make sure the water is getting through the mulch and into the ground.
Fertilize with a high-nitrogen fertilizer. Use one tablespoon of 10-10-10 per plant at planting time and again three weeks later. If your soil is high in organic matter, cut the fertilizer by half.
To protect them from aphids, cabbage worms and cabbage loopers, cover the crops as soon as they are planted with a lightweight row cover called Reemay. Bury a few inches of the material into the ground or anchor it with long boards - no loose ends. Aphids and moths can find their way through the tiniest of holes. Leave plenty of material on either side of the row.
As the plants grow, they will lift the material.
You may try planting for a fall crop, but the seedlings should go in by mid-July - the beginning of our long, hot, dry summer - everything broccoli detests.
If you can shade them and keep them cool and moist, it might work.
If it doesn’t work, consider it an experiment. If it does, it’s bushels of fresh broccoli. You can’t go wrong.
Q. What has caused the branches of my very old jade plant to become limp and the leaves to shrivel? - Liz, Spokane
A. The jade plant (crassula) is a succulent. It stores water in its branches and leaves.
Overwatering can cause root rot and stem rot. Once rot begins, water cannot move into the leaves. Thus the leaves begin to shrivel. How much water the plant needs depends on your house temperature and the amount of light the plant is receiving.
A good rule of thumb: Keep the plant on the dry side. I water my jade only when the leaves begin to shrivel. It may be weeks between waterings.
Overfertilizing also may cause stems to wither. Even though the houseplant books recommend fertilizing, I caution you to use a weak solution and only once or twice during the active growth cycle in the spring.
Because the jade is a succulent, never transplant it into wet soil. In fact, the soil should be light and fluffy and barely moist.
After transplanting, don’t water. The roots need a little time to callous and harden in. Wait a few weeks, then water only enough to dampen the soil.
Q. I would like to plant a windbreak. Can you suggest appropriate plant material? - George, Coeur d’Alene
A. Depending on the length and size of the windbreak, I would suggest stagger planting with different plants. Use a mixture of evergreens for the back row, along with some deciduous trees and a few shrubs in the front row. This will give you a full and interesting windbreak.
The following are suggested plants from the Pacific Northwest Cooperative Extension bulletin, PNW 5, Trees Against the Wind:
Shrubs: Siberian pea, common lilac, Peking cotoneaster and mugho pine.
Deciduous trees: Russian-olive, golden willow, green ash, Lombardy poplar.
Evergreens: Rocky Mountain juniper, Eastern red cedar or Virginia juniper, Austrian pine, Scotch pine and Norway spruce.
These are only a few suggested plants. If you would like a copy of this bulletin, please call Washington State University Cooperative Extension at (509) 533-2048.
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