Snow in Summer

What’s interesting right now? Snow in summer (or was that winter?). If you have full sun and good drainage, this plant is an excellent choice. Cerastium tomentosum (snow in summer) leaves are silvery and tomentose, or woolly, even in the middle of winter. This is a low plant that is great for growing over or through a rock wall.

In May you’ll be rewarded with snow – white flowers that completely cover the plant. If you provide excellent drainage and don’t live in the South, snow in summer will serve as a groundcover the rest of the year. If drainage is poor, it will probably rot and die. In warm summers (usually warmer than those in Indianapolis) the center of the plant will “melt out” – lose its leaves and look terrible. There’s not much you can do if this happens. Cut it back and hope the weather cools. If it happens repeatedly, then snow in summer is not a good plant for your area.

The pictures were taken in May 17, 2006 and mid-January, 2008. This plant is hardy in zones 2-7.

Some of My Favorite Winter Plants

Winter gardening articles are often about the future – planning the garden, new species and cultivars, the best summer vegetables. Let’s break out of the mold and talk about things that are exciting in the garden right now.

One of my favorite winter plant combinations is Italian arum (Arum italicum) and Lenten rose (Helleborus orientalis) (foliage of both shown to left). Italian arum has a life cycle that differs from most other plants. The leaves come up in October and look nice all winter. It doesn’t matter how cold it is or how much snow we get, as soon as the weather warms a bit, the leaves look great. The flowers leave a bit to be desired but give rise to a tall stalk of ornamental bright red-orange berries in late summer. As the flowers appear in May, the leaves die to the ground. If there were no fruit stalk, you wouldn’t even know the plant was there for most of the summer (note lack of leaves in photo below. The leaves you see belong to Lenten rose). In October, the cycle repeats itself. Lenten rose has more normal behavior, if you consider flowering in January to be normal. I’ve only seen that happen once. Usually the rose-like flowers are at their best in March, during Lent. The leaves are large, dark green and leather. They’re evergreen and in winter look great against the arrow-shaped leaves of Italian arum. As the new growth begins in early spring, the old leaves will turn brown and fall over. A quick clean-up will let you appreciate the flowers all the more.

Where do Plants Spend the Winter?

We’re all familiar with animal adaptations to winter. Many birds leave town all together to avoid cold weather. Some snakes hibernate, going underground. Other animals add a layer of fat or change the color of their fur, adaptations for survival in snowy terrain.

So, where do plants spend the winter? The simplistic answer is: the same place they spent the summer.

But, that doesn’t mean plants are the same in winter and summer. You may be surprised that plant adaptations are remarkable similar to those of animals. Annuals “leave” town for the winter, dying with the first cold. Their seeds go traveling, courtesy of animals and wind, and will “return” as new plants in spring.

Perennials go underground, storing food and nutrients in roots and underground stems. The tulips you have just planted and the potatoes and sweet potatoes you enjoyed with your holiday meals are examples of plants that create special structures to accomplish this task.

Trees and shrubs don’t add a layer of fat but add sugar instead. This creates a natural antifreeze within each cell that prevents freezing, even if temperatures fall below zero. We take advantage of this antifreeze and harvest the sap of the sugar maple in spring.

Some plants, like the arctic animals, change their look in winter. Trees shed leaves, an adaptation that prevents excessive water loss. The absence of leaves also prevents breakage that might occur with the weight of a heavy winter snow. In contrast, evergreens look the same all year long and, on a warm winter day, can function as in summer, converting sunlight and carbon dioxide into usable food.

The landscape can be a wonder in winter – a chance to admire the many ways animals and plants survive even the coldest days.

Picking Plants for your Garden

January and February in the garden? In Indiana, it’s usually January and February in the garden catalogs. Most serious gardeners – and even those who just want to add a few new plants to their yard – will be busy planning and researching, trying to decide which plants to choose. Here are some trusted on-line resources that can help your research:

The Kemper Center for Home Gardening at Missouri Botanical Garden has lots of information on the web. Go to http://www.mobot.org/gardeninghelp/plantfinder/alpha.asp to find a list of plants by their scientific name. You can browse by common names, too. Just click on “Common Names” in the ribbon at the top of the page. This website provides information on individual plants, including on a number of specific cultivars. The St. Louis climate is somewhat similar to that of Indianapolis, so a lot of the information is directly applicable.

If you’re looking for information on trees and shrubs, try the University of Connecticut Plant Database http://www.hort.uconn.edu/Plants/. You can select plants by their common or scientific names. The information appears to the left. Just click on one of the picture thumbnails, and it will be enlarged into the center panel.

Once you’ve decided which plants you want, where can you buy them? Many will be available in local garden centers. If you’re looking for something unusual, you may find a source on this website https://plantinfo.umn.edu/arboretum/default.asp, sponsored by the University of Minnesota Libraries. You’ll have the best results if you search for the scientific name (spelled correctly of course). I’ve used this site to find lots of unusual plants including tropicals, houseplants, and landscaping plants.