The species of ladybug, Cryptolaemus montrouzieri, is known to feed on all stages of the mealybug.  This species is already established in Florida and can be purchased commercially.  These ladybugs will provide some suppression of high pest populations, but they really don’t do that great of a job on controlling lower populations because they require a large number of mealybugs to survive.

With succulents like you have, those mealybugs can easily escape your pest control endeavors because they have lots of crevices to hide in.  Another idea is to consider using an insecticidal soap in a spray bottle, as opposed to the high-pressure watering method.  It’s a little milder approach to neem oil and it may be a safer bet for any chance of an overspray.  You’ll also probably be able to get to those hidden spots on your plants where the mealybug may be hiding.  And of course, it’s safe for the plant and the environment.  The only real disadvantage is that it has no residual effects, so you’ll have to spray a couple of times until you eradicate them and follow up periodically as a pro-active approach.

“Truth or fiction? Black walnut trees contain a substance that is toxic to many plants. If so, is there anything that will grow under them?  My tomato plants certainly did not do well by them.”

This toxic chemical you are referring to is called, juglone, and is present throughout the tree and does affect plants growing beneath and around them. I’d plant my garden away from them if you can, especially asparagus, sugar beets cabbage, peppers, potatoes and tomatoes. Azalea, hydrangea, lilac, roses and rhododendron, lily and peony plants do not do well under them either. On the other hand, snap beans, corn, grapes, onions, black raspberry and parsnips do okay, as well as begonias, irises, hosta, impatients, geraniums and morning glories.  I can attest to the hosta, irises and black raspberry through personal experience, and learned the hard way about tomatoes.

“Do you recommend any particular fertilizer over another for garden plants, flowering plants or lawn care?  I’ve been using the same fertilizers for years on my perennials and I’m just not feeling like my plants were up to par this year.”

That’s a pretty big question and unfortunately “one size does not fit all” when it comes to fertilizer.  Different fertilizers are used to promote different results in different plants, and of course different soil compounds come into play as well.  It’s a whole chemical thing.  Maybe it’s time to experiment with some different fertilizers for not only your plants but for your soil.  I stumbled upon a pretty neat product this year that I thought I’d try to give my normal, everyday annuals a boost.  It’s called SUPERthrive.  It is a fertilizer supplement, not a replacement.  I planted the usual vica, geranium, petunias and coleus in my outside pots this year, added some SUPERthrive to my usual Miracle Grow and Holy Cow!  My plants not only sprang to life, but filled the pots to the brim in no time at all!  Check out their website at www.superthrive.com.  This stuff is incredible. GG

Do You Have a Question about What’s going on in your garden or greenhouse?  Submit your question for Barbara Sue (include your city and state) by contacting us at: phone (563) 557-7571, fax (563) 557-7641 or email This e-mail address is being protected from spam bots, you need JavaScript enabled to view it or write us at Garden and Greenhouse, 6170 Forest Hills Drive, Dubuque, IA 52002.  Barbara Sue will do her best to publish your question with an answer in the next available issue.

Barbara Sue Schubert is a human resource professional, free-lance writer and a garden and plant enthusiast from southern Wisconsin.  “To me, HR and gardening have a lot in common, both feed my family!  Writing, on the other hand, feeds my soul.”