21 November 17, 2010
Hopefully, last winter taught gardeners the importance of mulching their gardens in the late fall. Last fall, we had a series of very cold days that froze the ground. A snowstorm soon followed and the ground was white for a few weeks. Temperatures soon rose and the snow melted and the ground thawed out. What followed for most of the winter were relatively warm days and cold nights. During the night, the ground froze and during the day, the ground thawed out. Come the spring, this turned out to be a major problem.
When the ground freezes, plants are lifted in the soil. This lifting action breaks off some of the roots. When the ground thaws, the plants settle back into the soil. If the ground freezes and stays frozen, this is not a problem. The amount of root damage is minimal. In the spring, cool days allow the roots to grow back before the heat of late spring.
Last winter the alternate freezing and thawing broke off many roots from our plants. This lead to major problems with the plants’ ability to take up food and water when spring arrived. If we had a normal spring with cool temperatures and rainy weather, the plants may have been able to put out new roots before the hot weather arrived. Instead, the weather warmed up early (with no complaints from the humans!) and plants were not able to take up the water and nutrients that were necessary for the plants to begin their growth. The result was apparent in the drying leaves on evergreens and the lack of flowers on spring flowering plants. Even normally hardy deciduous plants had stem and branch dieback. Many perennials had sufficient root damage preventing them from coming back.
Granted this was an unusual scenario for a New England winter and early spring. The problem is, we don’t know what the winter will bring. People will ask me” What do you think the winter will be like?” My answer has always been,” Check back with me in March and I can give you an answer!”
Ultimately, what we want to happen is for the ground to freeze and to stay frozen. The way you achieve this is to mulch the soil around your plants in late fall. What you need is 3 inches of mulch around the plants root zone. Even if you mulched your plants this spring, the mulch has broken down and you now will have less mulch.
Depending on the variety of plant, the root zone can extend out several inches from the base of the plant out to many feet on large trees. Most of your perennials will benefit from an application of mulch about 4 to 6 inches from the base of the plant. Small shrubs will benefit from an application of mulch extending a foot out from the base of the plant.
Over the years, we have all used salt marsh hay as mulch. The problems are that it is harder to find, it has to be removed in the spring and disposed of and there is some concern about having equipment on the marsh and the potential for pollution from the equipment used to harvest the mulch. For the past several years, we have been selling a product called Mainly Mulch. It is from Maine and it is a by-product of regular hay production. The hay is harvested, chopped up and dried and then sterilized to kill off any insects or fungus. It is packed in plastic bags. This makes for a cleaner product that is lighter in weight than a bale of salt marsh hay. The added benefit to using Mainly Mulch is that come the spring, it can be spread out in the garden and it will decompose into the soil.
The important thing is that now is the time to get mulching your plants for winter. Ideally, if the ground froze and we got a foot of snow to cover the ground and the temperatures stayed cold all winter, you would have to do nothing. Snow makes great mulch! However, this is New England. We don’t know what the weather will bring between now and April. Take the time now to mulch your plants for the winter. We all had plant damage this past spring. In some cases, the plants have not completely recovered from last winter’s damage. Mulching now may make the difference between you enjoying the sight of your plants springing back to life in April versus having to replace a lot of plants in April.
Well, that’s all for this week. I’ll talk to you again next week.