Meet Mike in Leesburg Next Month
Mike will appear at 11 a.m. and 1:30 p.m. on Sunday, April 19, at the Leesburg Flower & Garden Festival.
Where can I find corn gluten?
Ray writes: “I’m having difficulty locating corn gluten meal this year here in Northern Virginia, and I know it is very near time to lay it down. (I’m waiting for you to officially announce “now is the time”). I could order it over the Internet, but that would mean I might miss the application date. Any ideas where I can get some locally?”
As a general rule, you’ll find the best selection of natural and organic products at large independent garden centers — the family-owned places that have often been around for generations— as opposed to big-box stores.
Espoma, the people behind the well-known Holly-Tone brand, offer a nice corn gluten product at retail and have wide distribution. (If a store has Holly-Tone, they should have Espoma’s corn gluten as well.)
Bradfield Organics is another major retail brand you often see in our area. And you might even be able to find the newer liquid form of corn gluten at some locations. Developed by the same researchers at Iowa State University, it’s said to be more effective at preventing summer weeds than granular CGM.
Like comedy, the essence of crabgrass prevention is timing
Corn gluten meal — an all-natural byproduct of corn starch manufacture — is a perfect (and legal under the new laws in Maryland and Virginia) lawn fertilizer that also has the potential to prevent crabgrass and other summer annual weeds — if you apply it just before soil temperatures reach 55 degrees, as measured four inches down.
A visual cue to this temperature is the opening of the first flowers on forsythia shrubs and redbud tress. Of course, you can also buy a soil probe and follow your own personal temp daily — just remember that the probe has to placed four inches deep into the soil.
The temperature of the water in the bay also mimics soil temperature. Those temps were right in the low to mid-forties at last check. (To follow the flow live, go here and scroll down to the “water temp” column. ) You can also monitor the actual soil temp in Prince George’s County online. On Thursday, it had not yet topped 44 degrees. (Keep reading until the end of this week’s Garden Plot for the details on how to use this online resource, which requires some explanation.)
Bottom line: Get your gluten in hand, but wait another week to apply it.
Spring bulb care: Lose the old flowers, but leave the leaves
Spring bulbs are coming up all over. Heck, for some of you, the super-early-to-bloom bulbs, such as snowdrops, have already come and gone. That makes this the perfect time to review the after-care rules for those who hope to see those flowers again year after year.
First, be sure to enjoy the show of daffodils, tulips, crocus and such this season. We earned our reward for putting up with a second wicked winter in a row.
Then, when the flowers fade, clip off the very tops of the stalks to remove potential seed pods and direct all the plant’s energy down to the underground bulbs.
But don’t remove any of the green leaves. The bulbs need every one of those leaves to collect solar energy to fuel the growth of next year’s flowers — which will be fully formed inside the underground bulbs by the time the greenery dies back later this spring.
After the green is gone, you can carefully cut off the brown leaves, but not before.
Pansies bloom in the coldest spring chills
Baby it’s still cold some nights! But we need flowers! We know its spring, even if nature doesn’t seem to want to cave into that fact quite yet!
So what’s a gardener to do? Go out and buy a flat of pansies.
These colorful members of the Viola family don’t mind temperatures that drop below freezing, and will bloom like mad for you until summer heat finally does them in. (They’re the “polar opposite” of summer flowers such as marigolds and petunias, which crash when they hit winter cold).
And pansies are edible flowers. A handful of plucked pansy flowers can make a 50-cent bowl of lettuce look like a million bucks. Pansies are also one of the only food sources of Rutin — a nutrient that strengthens your capillary walls and thus prevents or reverses the visible effects of varicose and spider veins.
Just don’t eat the first run of flowers from a garden center flat: Wait until the second flush to make sure you’re not ingesting any sprays.
Step AWAY from the pruners
‘Tis the season of itchy fingers — so it’s time for me to issue my annual pruning warnings.
First, don’t touch any plant that blooms in the spring, such as (but not limited to) rhododendrons, azaleas, forsythia, flowering cherries and the like. The only safe time to prune spring bloomers is in the first few weeks after their flowers fade for this season.
Wait to prune roses until about two weeks after they start growing again. Remove anything dead or ugly, and prune to open the centers up to airflow. Be sure to remove any old mulch under the plants (it’s full of disease spores) and replace it with two inches of compost. Never use any kind of wood mulch anywhere near roses; it’s an invitation to disease.
Same timing with figs, crepe myrtle, butterfly bush and other “summertime” plants: Wait until they start growing again and give them a nice haircut. Be sure to remove any winter-damaged areas, especially from the figs — but don’t commit “crepe murder” by cutting that poor plant back too low: just a foot of two off the top.
And don’t touch hydrangeas until this year’s flowers are fully formed.
A complex resource for local soil temp info
Burt, in Rockville, originally turned me on to this resource: The USDA National Resources Conservation Services monitoring station in Powder Mill, Maryland, where you can see daily soil temperatures as measured 2 inches, 4 inches and 8 inches below the surface.
Thank you again, Burt. We have the best listeners here at WTOP.
Now, this site is a little tough to navigate, so here’s what you have to do:
- Open the page
- Choose “soil moisture and temperature” from the first column
- Go over to the 4th column (the yellow one), choose “last 7 days” and then click “view current” right above that. You’ll be taken to the page with the readings. (I tried like crazy to make a more direct link, but failed.)
- Today’s date will be the last one on the list, and the column that says “STO.I-1:-4 (degC)” (4th from the right) has the soil temp we’re looking for.
- But it’s in Celsius! Go here to convert it to Fahrenheit. Or do the math: multiply the Celsius number by 1.8 and then add 32.
- Start spreading your corn gluten when the soil temperature number hits 50 degrees F, so the material will be down and active by the time the soil reaches the crabgrass germination temperature of 55 degrees (or 12.7 degrees C, for all you metric fans out there…)
