Mulch protects plants from winter's wrath

11/29/2006

I've had my eye on the radar, and it looks like wintry temperatures are moving in later this week. And that means it is time to make sure plants are protected. But here's the trick: You don't want to cover the plants before they freeze; you want to cover them after they are frozen.

That may sound crazy, but if plants have been around for a while, they are used to freezing temperatures. The cycle of thawing and re-freezing will hurt them more than being frozen. Cover them with a thick layer of mulch after the temperatures stay below freezing for a few hours during the day and through the night.

Everything in the garden will benefit from a thick layer of mulch right now. Tender perennials or plants that were new this past summer should be mulched around the base. Put a four-inch layer of mulch over bulbs, and don't forget to put some mulch around the bases of trees. (Use an organic mulch and leave the rock mulch for a landscaping project next spring.)

Roses need special protection too. Pile manure around the base of the plant for a spring feeding. If the roses are in a windy area, put three stakes around the plant. The stakes should be taller than the plant. Secure a wrapping of burlap around the roses and fill the area with light leaves until next spring when you prune them.

Mulch is very handy. It helps hold moisture down in the roots of plants during the hot summer and prevents water from evaporating out of the soil.

It also keeps the roots cool in the summer and warm in the winter. I use a three to four-inch layer of mulch to smother pesky weeds and make the landscape look unified.

Mulch can also protect plants from disease. Scientists say plants can be affected by fungus and bacteria that splash up from the soil. Mulch can soak up the wet mud and cut down on soil-borne diseases reaching plants.

But mulch isn't always beneficial. I've had some nasty bacteria show up in my loads of mulch. If you pile the mulch too high at the base of the tree, rodents may build nests and feed on the tree through the winter. Slugs also like to hide in moist, wet mulch.

It comes in all shapes and sizes. You can use black plastic and rock mulch if you don't like to dig around in your garden. Rock mulch is also great if it is really windy in the yard. Bark mulch is popular for people who like to play in the dirt. A four-inch layer will help insulate plants, but using wood chips for long periods will suck the nitrogen out of the soil. Mix compost with bags of wood chips: one bag of compost to two bags of wood chips.

Hay and straw make good insulators, but you have to watch out for weed seeds. Sometimes they create more problems. Pine needles and peat moss also make great lightweight mulch. But too much of a good thing can be a problem. A continual thick layer of pine needles will make soil acidic. To make the peat moss easier to use, water it down even while it is in the bag.

Composted leaves are the best type of mulch for the yard so don't bag them up and throw them out. As leaves fall, chop them with a mower a few times, then rake a three-inch layer onto the landscape. They will break down quicker because they already are shredded, and they also protect plants during winter.