Dandelions, hydrangeas and tomatoes

Editor’s Note: Mike will reveal how you can have the best looking lawn in the neighborhood without Bay-killing chemicals at 1 p.m. on Saturday, April 21 at the original Homestead Gardens in Davidsonville, Md. On Sunday, April 22, he’ll teach you how to grow your best tomatoes ever at 1 p.m. at the new Homestead location in Severna Park.

Mike McGrath, wtop.com

Dandelions will drive you wild

Jan in Annapolis writes: “I have more dandelions in my lawn than anyone else in the neighborhood. They’re using treatments that I’m sure aren’t good for the Bay, and I’m tempted to do the same. Help!!”

First, take a chill pill, Jan. They’re flowering plants, not homicidal maniacs — at least, the dandelions aren’t. Soak the lawn well — it makes weeds super-easy to remove — and then use a device like the Weed Hound that pops the plants out of the ground, roots and all, while you remain standing. Another good option is the Water-Powered Weeder from Lee Valley Tools. It uses a super-sharp burst of water to blow the weeds out of the ground, roots and all — again, while you remain standing. Or, use a flame weeder, like Bernzomatic’s Yard & Garden Torch, to singe the flowers before they can go to the puffball stage.

Then, do not cut your lawn below three inches this summer and plan to aerate the turf this fall. Dandelions are a sure sign of scalped lawns and heavily compacted soil.

Frost-bitten hydrangeas

Lynn in Rockville writes: “My hydrangeas were starting to leaf out when we had that really cold frosty night, and the emerging foliage was killed. It’s leafing out again nicely now from the base and middle, but the top still looks dead. Should I prune off the dead tops or just wait and see what grows?”

This happened to virtually everyone across a 10-state region that chilly night, Lynn, including yours truly — and I now apologize to the ‘TOP listener who asked if he should cover his hydrangeas that night and I said ‘No.’ Oops.

Now, it’s really hard to predict where blooms are going to appear on hydrangeas and any pruning at this time of year can remove future flower buds. My advice is to wait until the plant’s flower heads begin to form. Then prune off any areas that still seem dead.

And, as I always advise, remove any flower-free branches that are blocking the blooms after all the flowers have appeared. That’s the best way to see the whole show.

Don’t plant tomatoes too early

David in Centreville writes: “When should I put my tomato plants into the ground?”

Not yet, David, that’s for sure. It’s still April, the nights will be frosty cold this Monday and Tuesday, and sub-freezing weather has occurred on these dates in the recent past. We’re typically not guaranteed to be frost-free until mid-May.

Besides, frost isn’t the only concern. Tropical plants like peppers, tomatoes, melons and cukes can be severely weakened by sitting out on cold nights, especially when the plants are young.

Wait until you turn the calendar page to May, and then wait until the 10-day forecast shows night temperatures staying reliably in the 50s. In the meantime, you can take the plants out on warm and sunny days. You can even leave them out on warm nights. Just be sure to bring them back inside on cool nights.

Get birds to eat your bugs

Patricia from Greenbelt writes: “Tell your listeners who have veggie gardens to put in a bird bath. The birds who use it will patrol the garden constantly for bugs. The bath has to be emptied on a regular basis to prevent mosquitoes from breeding in the water, but I just dump the old water right onto the garden.”

Thanks, Patricia. I’m pleased to report that I’ve been tossing this advice around for decades. Many birds, like wrens, chickadees, the nuthatch and the titmouse, are full-time carnivores who eat bugs for a living. The best way to attract them to devour your garden pests is with birdbaths in the center of that garden, as fresh water is often scarce in the summer. Heck, it’s been scarce this spring.

But don’t put out any birdseed or bird feeders. You want your feathered friends to eat bugs, not seed. And seed feeders attract mice, rats, voles and Evil Squirrels.

Puny boxwoods

Jim in Woodbridge writes: “I have eight boxwoods; four on each side of my front door. The ones on the right get a lot of sun and are healthy and large. But the ones on the left are much smaller and a paler shade of green. Is it because they don’t get as much sun due to a large maple tree in the center of the yard?”

Shade isn’t the only issue in these situations, Jim. Big trees also steal water and nutrients from nearby plants. But you might be a contributing cause. Boxwood requires a slightly alkaline soil, but people sometimes mistakenly give their boxwood a plant food that acidifies the soil, like Holly-Tone, because the products often say on the label that they’re good for ‘all evergreens’. Boxwood is the exception to that rule.

Try dusting some lime or wood ash around the scrawny plants to raise the soil pH, especially if you have so offended.

Remove any wood or bark mulch if it’s down there.

Do mulch all of the plants with an inch of compost — but no deeper than an inch. Boxwood has sensitive roots.

(Note: There is no such word as “boxwoods.” It’s just ‘boxwood’ no matter the number of plants.)

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