Meet Mike at Behnke’s in Beltsville next Saturday!
Mike will tell you everything you need to know to enjoy your best-tasting tomatoes ever and answer all your growing questions in a free lecture and Q&A from 1:30 p.m. to 3 p.m. at Behnke’s 5th Annual Garden Party event on Saturday, June 6. Details: http://behnkes.com/website/events-calendar.html
Prune This, Not That!
We have reached a very important time of year, gardeners: One of the few times I will tell you that you can prune — in fact, you should!
This is the only safe time to prune your azaleas, rhododendrons, forsythia, lilacs and other spring bloomers without risking harm to next year’s show. You can reduce their size by a third if they’re getting too big, otherwise, just prune off the areas where they had flowers this spring — it’s good for the plants. (Warning: Pruning after the July 1 can remove next year’s flower buds.)
But do not touch the leaves of your spring bulbs! Those green leaves have to be left alone to capture the sunlight that will fuel the underground growth of next year’s flowers.
Don’t tie them up either. “Bulbs in bondage” don’t get enough sunlight. Wait until the leaves have lost all their green, then you can gently cut them off at the soil line.
Be Especially Nice to Your Lawn Right Now
Rain has been scarce for most of us, temps have been unnaturally high, and many area lawns have been drought stressed for the past few weeks. Some that weren’t watered during our “invisible drought” have even gone brown and dormant — but they’ll green right back up again after the expected rain we have coming. (Unless you foolishly fed them chemical fertilizers while they were brown. Then they’re probably dead.)
Allow your grass to completely rehydrate before you cut it. And then do not cut lower than 3 inches (that’s the height of the grass after mowing). Scalped lawns die during dry heat waves.
Always leave the clippings on the lawn. Never bag them.
And never cut a lawn while it’s still wet. Cutting a wet lawn can ruin it for the rest of the season.
Being Lemony Fresh is a Great Mosquito Deterrent
University of Maryland entomology professor Mike Raupp made some very good points in a mosquito bite prevention article we ran earlier this month, including a nice mention of the best “alternative” mosquito repellent ingredient: oil of lemon eucalyptus, which the professor called “very effective.” One widely available brand that uses it is “Repel Lemon Eucalyptus.” Good call, prof, I agree! And more importantly, published research documents its effectiveness.
I’ll add that research has found that some actual garden plants can also work well if you know how to use them. Virtually all of the lemon-scented herbs have been shown to have mosquito repelling power when the fresh leaves are crushed up and rubbed on the skin. Sorry “mosquito-repelling plant” coupon clippers, but plants just sitting in pots don’t help.
Beautiful lemon thyme has been found to be the most effective of the lemon-scented herbs, but it’s a small plant, and you have to grow a lot to have a decent amount of leaves. But there are no downsides to that “warning” — it’s a fabulous-looking plant that is highly ornamental, especially trailing down from the edges of big containers.
The bigger leaves of lemon balm and lemon-scented geranium also work well. Warning — lemon balm is too easy to grow, and can become invasive if you don’t keep it under control.
Don’t use real lemons! All citrus — especially lemons and limes — can cause a nasty rash if the rind is rubbed on the skin.
‘Evil Squirrels Eat My Peaches!’
Edwina down in White Plains writes, “We planted peach trees several years ago. Every year, the squirrels get the peaches before we do. What can we do to keep the squirrels away?”
Those long-tailed servants of Satan are tough foes, Edwina. Try aiming a motion-activated sprinkler at the trees; the evil squirrels don’t like getting hit with the bursts of water it shoots out when they approach. I’ve always recommended the original “Scarecrow” brand, but judging from the reviews, this “Orbit Yard Enforcer” may be even better.
Now — I presume you’re pruning the trees every spring and have been removing three-quarters of the fruits while they’re still little. You have to do both of these chores to get good peaches. (Or apples — both are “hard work” plants.)
After you’re done thinning the fruits, begin spraying your trees with “Surround,” a micronized clay that protects the developing fruits from insects and disease. It turns the trees a silvery-grayish white, which in my experience, seems to make the peaches less appetizing to the terrible tree rats. I spray about once a month and get a nice big batch of peaches for my reward.
Maple Tree Double Whacked by ‘Lawn Care’
A couple weeks ago we told Diana in Alexandria, Virginia that her abundance of maple seeds could mean that the tree is under stress. She now writes, “It appears that our huge maple is indeed stressed about something. The leaves are puny and ragged, while our next-door neighbor’s tree is normal.”
So I asked her my standard tree-stress questions: Is it fed? (Best answer: no.) Is it mulched? (Best answer: no; second best answer: yes, but the mulch doesn’t touch the trunk of the tree.) And is it growing in or near a treated lawn?
Unfortunately, she got the first two right but then acknowledged that yes, they had recently treated the grass with a “plus two” product from a company whose name starts with an “S.”
Unfortunately, a little research on this product reveals that the “two” refers to two different chemical herbicides, one of which is the notorious 2,4-D — a known cancer causer that was a component of the infamous “Agent Orange” defoliant used in the Vietnam War.
These kinds of so-called “pluses” can be a big minus for nearby plants, as the herbicides are designed to kill pretty much anything that isn’t a lawn grass. All she can do now is keep the tree well watered, don’t use any more chemicals on or near it and hope for the best.
Oh — and as I have preaching for 16 years on WTOP — lawns do not need chemical herbicides. The only way to have a weed-free lawn is to take correct care of the lawn.
A Non-Toxic Way to Spray Away Wasps
Cam up in Elkridge, Maryland writes, “I have three small ‘hives’ being built above a doorway near my garden. One has two or three bees or wasps on it. The others are small and gray, and one has a ‘baby sitter’ that chases me away. I don’t think they’re bees, but they do have a black and yellow pattern. I want them gone; this has been scary for me.”
Well, based on your descriptions they could be paper wasps or they could be hornets beginning to build a big football-shaped nest. Either way, I personally try to leave these creatures alone whenever possible, as these kinds of insects eat a lot of caterpillar pests. (“The farmer who destroys the hornets’ nest harvests no cabbage or broccoli that year.”)
But they are stinging wasps, and if you have to use that door, you will get stung sooner or later. But there’s no need to expose yourself to poisons. Instead, heavily spray the nests and any wasps with a no-stick cooking oil, such as Pam. Be sure to use an aerosol product for this, not a “pump” container; the pressurized spray of the aerosol pushes them away from you as the oil smothers them, rendering them immediately helpless. They die soon afterward.
But again, if they’re nesting in an out-of-the-way area, leave them alone. Unlike the very dangerous yellowjacket, these wasps don’t want to sting you. But they do want to devour your tomato hornworms, leaf rollers, squash vine borers and cabbage loppers.
