Garden Talk: Do mushrooms at a tree base need to be removed?

Jill and Rick Van Duyvendyk answer all your gardening questions in Garden Talk on 650 CKOM and 980 CJME every Sunday morning from 9 a.m. to 11 a.m.

Here are selected questions and answers from the Oct. 6 show:

Garden Talk listener Ross from Saskatoon has a problem with mushrooms growing at the base of a lilac that was pruned. (Submitted)

Q: I have a lilac I pruned down a couple of years ago. Mushrooms have proliferated around the base where it was pruned. Should I remove the mushrooms?

A: The mushrooms are feeding on decaying wood. Take them off because they have grown right around the trunk of the tree, and will rot the bark, eventually causing the top of the tree to die. Spray with garden sulfur or copper sulfate, which is hard to get right now, to help prevent fungus from growing.

Applying a compost accelerator around the trees would help eat away the dead wood quicker so the mushrooms won’t grow. Once you take the mushrooms off, look at the base, and get rid of as much of the dead rotting wood as possible.

Q: My overgrown lilac tree needs pruning but it still has leaves. Can I still do that this year or do I need to wait until spring?

A: It depends how much you’re going to trim it. If you just want to do a light pruning to keep it in shape, the best time to trim it is right after it finishes blooming in June. If you want to do a major pruning, like taking a 12-foot lilac down to six feet, do it when the plant is dormant.

Read more

• Garden Talk: To prune or not to prune?
• Garden Talk: Do purple apples really grow in Saskatchewan?
• Garden Talk: Plant tulips now for spectacular spring colour
• Garden Talk: Don’t let Saskatchewan winter kill your water garden

Q: How do I make sure my new perennial bed survives the winter?

A: Wait for the leaves to turn completely yellow and then cut them back to the ground before adding mulch around the plant, either wood chips or dry leaves. Wet leaves can add some fungus.

Leaves can be put in a white garden bag and shaped like a pillow. Put it on top of perennials after you cut them down, weigh it down with a rock on top and in spring it’s easy to pick up with no mushy leaves.

Perennials grow back from the ground every year, so you do have to cut them back
to the ground, but this can be done in fall or spring. In the spring, the leaves are all mushy and fallen over, so it’s harder to cut them in the spring sometimes. But the advantage of keeping them is you have more debris for the snow to be caught on.

It also depends on what perennial we’re talking about. Hostas turn into like soupy muck after a winter under the snow. Some Zone Four perennials, like heuchera (coral bells), are more frost tolerant and can get some pretty colors on them with the frost. I like to leave Karl Foerster grasses unpruned in winter because I love the hoar frost on them.

See Dutch Growers guide to planning a perennial garden here.

Q: When is the best time to prune 10-foot Colorado spruce trees?

A: Pines can be pruned right now. We’re getting getting to the end of pruning birches and
maples, because if they are pruned later in October or November they can bleed in the spring. Elm trees can be pruned from Sept 1 to April 1.

Q: Is it okay to use rotten leaves and twigs from Caragana bushes for mulch in your garden?

A: The only time you wouldn’t use them is if you have some sort of disease on them, like a powdery mildew or a fungus, or if the plants have a really bad bug infestation. But otherwise, if you lay the leaves and twigs down on the ground, it will eventually turn into compost.

Q: What do I do with 1,000 broken elm branches scattered all around my yard this morning after the wind storm?

A: One thing about elm is that you can’t compost it, and you can’t store it. It has to go to landfill. Storing it attracts the elm beetle, which could bring Dutch elm disease.

Q: Should I wrap two young apple trees with burlap for the winter?

A: There are only two reasons to wrap with burlap — to keep rabbits and mice off them or to prevent sun scald. With the smoother, younger bark trees can get sun scald on the south side caused by reflection off snow, so burlap wrapped around the bottom part of the trunk will keep the sun off of them. Burlap has lots of holes, so the tree can still breathe. Wait until the snow comes to wrap.

Q: I have two Thunderchild crabapples which are beautiful trees but the fruits are a problem on the lawn. Is there anything we can do to the tree so that it doesn’t produce the fruit?

A: No. There is a product available in the U.S. that damages the blooms so that they don’t produce, but you can’t get it in Canada. If you do a light pruning on the trees when they are in bloom you potentially also remove apples as well. You could try spraying garden sulfur on the blooms in the evening, so any bees are gone.

You’re not the first person to ask that question. That’s why we sell so many Spring Snow, flowering crabs, because they have tons of white flowers and the plant is sterile and doesn’t have fruit. We also sell a tool that is like a little cage that you roll across the lawn to pick up all those little apples.

Q: What’s the best way to protect boxwoods over the winter?

A: Take a cardboard box and put that over top of it and fill it up with dry leaves to protect them from the sun and insulate them. The sun will desiccate them. Boxwoods are a Zone Four or Five, so they’re really tender in Saskatchewan. Give them a light pruning in the spring to get some new growth on them.  If you use burlap make sure that you leave it about six inches off the ground so you get snow covering the roots.

Q: I dug up my strawberry plants because I am moving in three weeks. Do I keep them in a cool, dark room till next spring, or replant them when I move?

A: What do we do? Replant them in three weeks, water them in and then mulch them really heavily by the end of October. If that isn’t an option, you can take the soil off and store them bare root in a cold storage area. You’ll have better success if you plant them into the ground as long as you mulch them.

Q: How do I store green tomatoes so they ripen slowly?

A: Take them off the vine and put them onto paper or cardboard and make sure the fruit is not touching. A cold storage area that is three to five degrees is the perfect temperature and it has to be dark. Light will make them ripen faster.

Q: How do I get rid of the crickets that are eating their way through my garden. They get in the potatoes before I even have dug them up.

A: That’s a tricky one. You could try little sticky traps or diatomaceous earth spread around the base of the plants. Diatomaceous earth gets into the joints of insects and dehydrates them. Garlic spray works as well. Planting garlic and chives among your potatoes is a good idea.

Q: I do no-till gardening. Is it okay to put sheep manure on rows?

A: Yes, except don’t put sheep manure where you will plant potatoes are. If it’s well-rotted sheep manure, you can put quite a bit on. Add it in when you plant, but don’t put it
right up against the seed. If it’s planted right up against the seed, it might be too hot for the seed when it first germinates.

These questions and answers have been edited and condensed.

Read more

• Garden Talk: To prune or not to prune?
• Garden Talk: Do purple apples really grow in Saskatchewan?
• Garden Talk: Plant tulips now for spectacular spring colour
• Garden Talk: Don’t let Saskatchewan winter kill your water garden