Gardening

Winter Interest Plants for Iowa; Part 1 Perennials/Grasses

We have reached that time of year once again – winter, even though lately being in the 50s, it sure doesn’t feel like it! Despite the mild weather so far, our landscapes are still dormant, and the “bones” of the garden are starting to surface. The bones, which are a very important part of any landscape, are the rocks, plants and other items that can be seen at all times in summer or winter. In many cases, evergreen shrubs are used as the bones, and in the past it has been, for the lack of better words, those “prickly pine shrubs” with needles. However, I’ve noticed that now people are tending to go away from using these traditional methods for adding winter interest. In part one of two posts, I will focus on plants for winter interest that are new and interesting, and with so many choices, why not choose something different!

120207_winter

Iowa has an interesting split climate, in the sense that southern Iowa is warmer and trends to be a typical winter, being in and out of snow cover all season long. Northern Iowa is much colder and normally has snow cover continually from December through mid-March. These types of snow cover will determine the type of winter-interest plant is the best for your yard. For instance, if you use a ground cover type in north Iowa, it will be buried under snow where you can’t see it, so taller plants should be used, at least as far as winter interest plants are concerned.

Grasses

Big Blue Stem
Big Blue Stem

Evergreens get all the attention, so I’m actually going to start with grasses. Grasses are one of my favorite winter interest plants and they are becoming very popular, and for good reason. They bring a new look to the winter garden and they hold up very well in ice and snow! They can be flattened by snowstorms, only to pop right back up when we get one of our thaws. They also turn beautiful shades of all colors in the fall, which holds through the winter. Depending on which type you go with, they can turn reddish to yellow and look great in a freshly fallen snow cover! Not only are the colors very pleasing, but many of the grasses produce a seed head ranging from fluffy puffs to interesting branched structures that wave gently in the wind. I especially like the use of grasses in Iowa because of Iowa’s prairie heritage. I am a believer of using plants in landscape that tie into the horticultural heritage of the area surrounding the garden. Grasses can be used as focal points in the landscape, as screens or accent plants. At the top of the post is Switch Grass, and featured below is Big Blue Stem grass, both of which are native to Iowa. Below I have grasses listed along with their fall/winter color.

Little Blue Stem
Little Blue Stem

Natives

Switch Grass – Yellow
Big Blue Stem – Red
Little Blue Stem – Red
Indian Grass – Yellow
Prairie Drop Seed – Tan

Non-Natives

Maiden Grass – Yellow
Purple Flame Grass – Light Red
Hardy Pampas Grass – Straw Yellow
Karl Forester Grass – Straw Yellow
Moore Grass – Yellow
Fountain Grass – Yellow (Southern Iowa Only)

Evergreen Perennials

Lenten Rose
Lenten Rose

Some perennials in our area are actually semi-evergreens! Most of these are shorter in nature, only about 3-7″ tall. Although hardy to the entire state, for winter interest reasons, they are best for southern Iowa landscapes where snow doesn’t last continually. One such good example of an evergreen perennial is this Lenten Rose. These plants hold their leaves all winter long. The leaves of this plant technically semi-evergreen, which means that in harsh winters they can look a little tattered by the end. The leaves can be trimmed back in spring and new growth flushes out, just like the rest of the typical perennial category.

Semi-Evergreen Perennials

Lenten Rose
Creeping Phlox
Prairie Smoke
Dianthus
Beardstough
Grape Hyacinth
Creeping Dianthus
Lungwort
Yucca (Most evergreen-like)

Non-Evergreen Perennials

BeeBalm
BeeBalm Seedheads

Most of our perennials fit into the non-evergreen category, however even some of these have great winter interest! Take a walk out in your garden and just take note at how beautiful some of the seedheads of many perennials actually are! Many plants have interesting structure and the coolest seed pots – this is why I choose to leave most of my perennials un-trimmed in the fall. In late fall, I go through and trim up the perennials that I don’t have much interest in, or are fallen over – and leave the rest. Not only will you get winter interest from leaving these plants out, but old plants will help catch snow, which is a great insulator in cold years. The only case in which I recommend cutting off in the fall is if you are dealing with fungal diseases. Peonies would be one of those plants I always cut back in Fall. Below are just a few of the winter interest perennials, try leaving some in your landscape and see what you like!

Winter Interest Perennials

Beebalm
Seedum
Coneflower
Rudbeckia/Black Eyed Susan
Iris
Lavender
Salvia
Globe Thistle
Achillea
Silvermound
Snowberry
Astilbe
Clematis
Aster
Catmint