Wintering Over Perennials

This is kind of a follow-up to one of Sue's questions from my last Blog, while it is rather incomplete because I do not do a lot these are a few of the things that I usually try to do for some of my plants. I have recently change what I do based on some of my appreciation for beneficial insects and birds so keep that in mind as well when you read this.

Getting your garden ready for winter is important to the health of your plants. How and when one cut things back is determined by the individual needs of your plants, your desire to provide food and cover for wildlife, and your appreciation for winter interest.

In years gone by I use to cut everything back to the ground for a neat appearance. Then I began to realize that butterflies lay eggs on leaves, birds feed on seeds and berries, and many animals use plants as cover. I also discovered the beauty created by seed heads; grasses and perennial stems left standing for winter can be a form of a winter garden. So now my desire for aesthetics has been replaced by a concern for wildlife has changed this urge to snip everything in sight.

So now my question is, should I cut anything back? The simple answer is, yes. Plants that had a serious disease or insect infestation should be cut back and the trimmings bagged with your trash.

Plants with no winter interest should be trimmed, too and recycled when possible. Some examples would be plants like veronicas or geraniums that blacken and turn to mush at the first cold snap. Also cut back plants that vigorous reseed themselves. Some of my plants would take over my whole garden if I did not use a firm hand in fall trimming.

Here are five categories of plants that should not be cut down for winter. First, any plant you feel contributes aesthetically. Grasses give wonderful architecture to the winter garden, so wait to cut them back until spring. Interesting seed heads and branches of arching perennials and shrubs also add winter interest, so spare them, too. This is all very subjective; so cut what you do not like and leave what appeals to you.

I usually do this with my grape, that way the birds can feed on the grapes and also allows me a few months before I have to do it.

Try to avoid cutting back tender perennials or ones that are not reliably hardy such as mums, asters and ferns. The old foliage helps to protect the crowns through winter. Show discretion when cutting back plants that are late to show in the spring; some plants are notorious for worrying gardeners by sprouting later. So leave a good chunk of their stems to mark their location so you do not disturb them or plant something on their heads.

Some plants such as sun drops have attractive evergreen foliage at their base. If you prune these plants well throughout the summer, there is no need to cut them back further. Let their whorls of foliage bring a little color and beauty to your winter garden A few shrubs bloom best on new wood. The butterfly bush, for example, will bloom more heavily if you wait to prune them until spring. Spare them a fall cutting and they will deliver winter interest and a bountiful flush of new growth and blossoms.

The timing and method of cutting plants back for winter is important, too. Later is better, generally. If plants are cut down too early, it can stimulate growth, use up energy reserves and keep the plant from coming back in the spring if a hard frost hits the tender new foliage. So, avoid cutting back plants too early. This is good for those of us who are procrastinators to one degree or another.

It use to be that people would wait until the first hard frost - as early as October or November in some areas - but I usually start my fall clean-up whenever it starts to get cooler in late October or early November.

For many years I did not do not do it until December or January, but that usually had more to do with my annual two weeks off at the end of December when I worked at Boeing.

Another question is always, how low should one cut? A good rule of thumb is two to three inches from the ground. That leaves some stems to act as a marker and avoids damaging the crowns or any over wintering buds that may lurk at or just below the surface.

With the cooling temperatures and falling leaves, fall gardening is a real pleasure. Preparing your garden for winter with an eye toward preserving beauty and wildlife will make it a task that adds valuable habitat and attractive winter interest.

I guess I got a little carried away with that and a little bit down a rabbit trail. So getting back to Sue's question, something else that one can do with the leaves that they have raked up is using them for mulch.

In gardening, winter could be defined as the time of year when most perennials become dormant. This time can vary from early September in some parts of the country to late December and beyond in others.

Cold is the major factor inducing plant dormancy. Thus, in preparing for winter, it is crucial to understand just what kind of cold affects your garden.

Snow, sometimes called a "poor man's mulch," forms an insulating blanket on the garden. Temperatures in the ground beneath the snow cover always hover around the freezing point, while they can plunge below freezing immediately above the snow line. Perennials that are dormant at a constant temperature rarely have trouble surviving winter months.

However plants in areas with little snow cover can suffer during unexpected or unusual cold spells. These need a 2 to 3 inch winter mulch; preferably an organic one, such as shredded leaves, fir/pine needles; several layers of B&W newspaper could be used in a pinch, but it does not work as well unless it is kept wet as it has a tendency to want to blow around.

The mulch protects plants from unusual cold spells and helps to maintain a uniform temperature so that the soil does not thaw out prematurely and expand when encrusted with frost or ice particles.

Before one adds mulch in winter, make sure your garden bed is as clean as possible. Clear away dead foliage and pull out all weeds. Then spread the mulch just after the soil freezes.

Now, you can step back and take a look at your garden and enjoy it knowing that you will not have to work in it for a few more months. If you have been considering improvements, decide where you would like to place new perennials and put some kind of markers in those areas. You might even want to write the name of the intended plant on each marker; this will make your spring planting a little easier.

Well, I am sure that there is a lot more that I could write about but not wanting to bore anyone to death I will put a close on this chapter of wintering over perennials at least for now.