Gardening Q's and A's

By Melanie Mathieson
Gardening Guru

Listed are four questions I recently received from area gardeners. I hope the answers I provide are helpful to you too.

Q: I have little green worms on my geraniums that eat holes in the buds. What should I do?
A: The worms you are seeing are most likely cabbageworms. Besides vegetables from the cabbage family, cabbage worms also feast on geraniums, sweet alyssum and nasturtiums. You can use a commercial pesticide like safers soap or a brand containing pyrethin (a natural insecticide developed from the chrysanthemum plant). A solution of a mixture of 1 tablespoon of Sunlight dish soap mixed into one gallon of water and washed onto the leaves is also effective. Remember to stick to the soap to water ratio so you do not burn the leaves. Or you can pick them off by hand. Because fo the recent moist and humid conditions this late spring caterpillar pests that like warm humid conditions will be at their peak this year. Some good housekeeping of your plants like trimming of any dead parts and deadheading the spent flowers helps to keep the pests away. When grooming (weekly if you can) look closely for the cabbageworms and just snip them in half with the scissors or pick them off and dispose of them in a can of hot water. Keep that in mind if you are trying to attract butterflies to your garden, cabbageworms do become pretty white butterflies.

Q: Mushrooms are growing in two different areas in my flower garden and in my lawn. What could I use to kill them?
A: Mushrooms are a sign that you have a lot of decomposed material in your soil and that’s good. Usually they appear after damp, rainy spells or if you water often. With the recent rainfall and if moist conditions continue you may see a bumper crop of many species of mushrooms this year. Mushrooms won’t hurt nearby plants nor deplete your soil of nutrients. If you find them unsightly you can gently rake them with a small cultivator or hand rake, but you shouldn’t be spraying them with anything to kill them. Sometimes when you first apply composted manure to your gardens mushrooms appear but after a few months they disappear. In an area that I mulched with pine bark I had a crop of morels in the spring for a few years. That was a real treat as I actually picked them and ate them. I do not recommend picking any mushroom for eating unless you are more than 100% sure of the variety and whether it is poisonous or not.

Q: I have some plants (pansies) in my flower bed that keep coming back year after year, but all the books say that they are annuals and have to be replanted every year. Do I have a special perennial version of this plant?

A: The short answer is no. Many annual flowers when left in the flowerbed until late fall will produce seed that falls on the soil. If the flowerbed soil is left alone or only disturbed slightly the following spring, these seeds come to life and produce new plants. This does not make the plant a perennial. This is just a plant that has self-seeded and produced new plants the following season. Many plants such as annual poppies, pansies, violets (Johnny jump-ups), annual alyssum, annual phlox, zinnias, hollyhocks are all common annuals that some people think are perennial because they come back each year, when in reality it is last fall’s seeds that have produced new plants.

Q: We have a tremendous amount of weeds coming up between our patio stones. What is the best way to get rid of them?
A: White vinegar. Spray all the weedy areas with full strength white vinegar. Vinegar is vinegar, so brand or price is not important, but pickling vinegar is even stronger in acidity so it is more effective. The acidic makeup of vinegar will burn the leaves of the weeds, killing them. The vinegar will remain in the soil for a while helping to deter the return of the weeds. Sometimes crab grass and dandelions can persist and need a second dose. Vinegar is safe to spray around pets and children but be careful to spray only on weeds as it can kill any plant you apply it to. Also great for maintaining weed free rock gardens that do not have other plants.