How much longer will new grass grow?

Richard in Manassas writes: “I was late, and so it was the first week in October when I finally got my first-ever core aeration and over-seeding done. I now have very fine new grass blades extending about an inch above ground level; but the roots are down in … aeration holes where the rain washed the seed — isn’t gravity cool? We’ve already had several frosts, and I was wondering how much longer my new grass can be expected to grow this season.”

It will grow for quite a while, Rich — the cool-season grasses that predominate in the region love chilly weather.

But we need to level the field here. Find a source of high-quality compost and slowly fill in the aerated holes so that the soil surface in them is level with the rest of the yard by spring. Just add small amounts at a time — don’t do it all at once. This won’t harm the new grass one bit (in fact, it will give it a slightly deeper root system, which is good), and a level surface is crucial for a good cut when spring and summer arrive.

Are freshly shredded leaves OK for trees and shrubs?

George in Vienna writes: “Did I make a mistake? I used a leaf blower set on reverse to shred my leaves and then worked them into the existing old bark mulch around my shrubs and trees. But I just read online that freshly shredded leaves are too acidic for immediate use and should be composted until the spring. Should I gather up the newly created mix and wait until spring to put it back?”

There’s some wacky stuff online, George. Those shredded leaves make a perfect mulch for your plants — there’s no acidity issue whatsoever.

But no mulch should be deeper than 2 inches or it’ll prevent water from getting to the roots. So if you really piled it on, thin it out to no more than 2 inches deep. And no mulch should ever touch a plant. So if your mulch mix is piled up against your plants, hoe it back a few inches. All plant trunks and stems should be untouched and open to airflow, just like in nature.

Proper plant practices prevent problems

In our last thrilling episode, we reassured George in Vienna that newly shredded leaves would make a great mulch for his shrubs. Now he adds that “all the shrubs are new this year, as my old cherry laurel bushes were devastated by a white powdery substance on their interior branches, dead sections, and yellow spotted leaves. I am nervously trying to not make any mistakes.”

Well the wood mulch that you admit to using previously was a big mistake, George. That junk kills plants.

It also sounds like your plants may have been fed with chemical fertilizers. If so, stop it! Trees and shrubs need no artificial fertilizer, and strong chemical “plant foods” actually make them weak and prone to the kinds of problems you describe. Feed new plantings with a 1-inch mulch of high-quality compost, not chemicals.

And the mildew you describe strongly suggests that your old plantings were way overcrowded and perhaps even constantly wet. Make sure that all your plants have good airflow between them, especially if they have to cope with shade. (The less sun they get, the more airflow they need.) Don’t overwater them — again, especially if they don’t get a lot of sun. And make sure that they’re pruned at the right time of year to keep them open and airy inside. That’s immediately after flowering for spring bloomers, and dead of winter or early spring for the others. Prune NOTHING in the late summer or fall — ever, ever, ever.

Put the lime in the coconut…

Johnny in Montgomery County writes: “I’ve gotten conflicting answers to the question of whether or not to lime my leaf compost. Can you give your regarded opinion on this matter? Also, is there a way to speed up the decomposition process?”

There’s no conflict here, Johnny — anybody who tells you to add lime, fertilizer, wood ash or other junk to your compost is wrong, wrong, wrong. You want a second opinion? They’re ugly, too.

Now, the best way to turn fall leaves into compost fast is to shred them up into the tiniest pieces possible — maybe run them through a shredder or leaf vac twice instead of just once. Then mix lots of spent coffee grounds in with those double-shredded leaves as you build your pile. Those leaves will become compost super-fast.

Garlic sprouts are a sign of success, not sadness!

‘J Nelson’ in Arlington writes: “We planted a garlic bed in early October. But the cloves sprouted and the stems are now about 8 inches tall. Should I pull them out and start over? Or will they produce anything meaningful for next Spring?”

Sure, you can pull them out — if you insist on snatching defeat from the jaws of victory, Jay. Those sprouts are a sign that your garlic is strong and healthy and developing a good root system for the winter.

So do nothing now!

In the spring, do nothing.

Then, when little bulges appear at the tops of the stalks (typically in late May), trim these “scapes” off and eat them. (They have a deliciously mild garlic flavor.)

Then harvest your garlic in late June or early July, when the leaves have turned brown on the bottom third of all your plants. Not before, and not after.

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