I would like to continue the discussion of adding winter season interest to your garden. In this post I will discuss of the use of architectural plants. This was suggestion #4 on my post a couple of weeks ago.
The first thing you might ask is what is an architectural plant? By this I mean a plant that has an unusual and distinctive form when compared to surrounding plants. This is mainly related to the branch structure which will be visible in the winter. It will often be covered with snow or ice to further draw attention to it. Some of the forms that fit into this would include:
2) Horizontally tiered
When picking plants with any of these forms, be sure than the bark is indeed an attractive color in the winter. It does not have to be red or yellow, brown is fine. You just want the bark and stem color to not be a dull grayish in the winter as this will be less visible.
Weeping plants are probably the most commonly used architectural plants. These include narrow growing forms with weeping branches such as the Purple Fountain Weeping Beech or Weeping White spruce. It also includes plants that are wider growing such as the Weeping Norway Spruce, weeping crabapples, or Japanese Maples.
Weeping plants can be great specimen plants that are the focus of an entire landscape. They have a lot of visual weight and hence their use needs to be limited. Too many of these form of plants will make a scene seem busy and chaotic. In most cases you don’t want to use more than one. One classic use of weeping plants is to place one on the edge of a pond and have the trunk lean over the pond.
These are plants that have a horizontal branch pattern such as Pagoda dogwood or Doublefile viburnum.
Horizontally tiered plants do not have as much visual weight as comparable weeping plants. They do still draw the eye to look at them though. Depending on the size of the plant, these should be either used as a single specimen or smaller shrub forms can be used as accents repeated throughout the garden. Two or three dwarf Doublefile viburnums placed throughout a landscape can provide a nice amount of repetition and tie the garden together.
These are plants that grow straight up. They are typically narrower and fit into smaller urban lots better than their non-columnar counterparts. They often impart a formal feel to the garden. They are often used as architectural plants in the formal gardens of Europe. They can be narrow plants such as Hicks Yew which only grow 3-4 feet wide, or could be pine trees that only get 15 feet wide and 40 feet tall instead of 40 feet wide and high.
Columnar plants are often used as groupings that can serve special purposes such as screening of a view or otherwise creating a wall in the garden. When they are used by themselves they have a tremendous amount of visual weight due to their strong vertical element. So much so that you often cannot help but look at them. Use these plants individually only if this is what you are looking for.
There are other forms that are unique to specific plants such as the spiky Yucca’s. These are unique and in my mind usually look out of place in the Midwest. They can’t help but invoke a dessert like feel. Someone from the Southwest who has moved to the Midwest could build an entire garden theme around them and boulders to evoke a feeling of being home. They are also often used in gardens designed using a minimalistic design. They do stand out like few other plants in the winter.