Foundation Plant Origins and Purpose
The tradition of foundation planting evolved from a desire to ease the transition from house to landscape or to disguise masonry and basement windows. Shrubs were the perfect solution. However, foundation plantings can present an occasional problem, usually in older homes. The main problems usually result from shrubs or trees that are too close to the house.
On the structural side, several things can occur:
- Some plant roots are quite strong and persistent. Years of growth can cause damage to the house foundation, resulting in a leaky basement.
- Roots absorb a lot of moisture and may result in overly dry soil at the foundation. The soil may pull away from the structure and allow water to seep in.
- As plants mature, the increasing height and width boost the chance of mold or mildew on house siding, requiring cleaning or painting.
- Taller plantings decrease the lifetime and effectiveness of gutters and roofing, and can interfere with utility lines aboveground and belowground.
Concerning the plants themselves:
- When shrubs are planted too close to the house or each other, drastic pruning is often required to keep growth under control. The natural shape and form of the plant is altered or disfigured.
- Planting too close to the house or other plants decreases air circulation. These plants are also more susceptible to pests and disease.
- If one or more of the above situations exist, start thinking about replacing or renovating your foundation plantings.
Removing mature plants can be difficult. If you want to transplant a shrub to another spot, a great deal of careful digging will be required to excavate the root ball without causing damage to the plant or the house. The resulting mass will be extremely heavy, so be prepared with the proper equipment to relocate it. A backhoe or skid-steer may be the only recourse.
After removal, whether you transplant the shrub or it's simply not salvageable, you're faced with a large hole right beside the house. When you dig out a shrub, have something ready to put in its place. If available, use subsoil (or fill dirt) to fill in the lower portion of deep holes. Fill dirt is less porous than topsoil. Fill to about 8 to 10 inches from the top of the hole, tamp it down and finish filling with a more root-friendly topsoil. If you're installing another plant, make sure you locate it so that it won't be too close to the house or other plants. Don't repeat the same mistake you're trying to fix.
Observe and address drainage problems near the foundation at this time as well. Soil should slope away from the structure. Building codes vary by region, but a 6-inch slope in the first 10 linear feet measured out from the foundation is a relatively common standard.
New homes present an easier project, since installing landscape plants is one of the last steps when a new home is completed. New homeowners have the ability to start with a blank slate. Read on for foundation planting ideas to help you with your planting design and execution.
Before beginning any excavation, call 811 to check for underground utilities.
Planning and Designing Your Foundation Garden
To achieve maximum visual impact, it's important to know the basics of landscape design. Incorporating scale, balance and variety will visually integrate the house with the yard. Whether your home is formal or informal, your plant choices should match the house's design. The goal is to enhance its appearance, not hide it. Many homes don't need a ring of shrubs around the front in order to be attractive. There are, however, some key areas of placement you may want to consider:
Entryways are focal points of the home's exterior, incorporating the areas that are in public view. Introducing accent planting is a wonderful way to draw attention to spaces that you want to highlight. Here are some suggestions for additions or improvements to make your entrance interesting and attractive throughout the year:
- A specimen tree with accent lighting
- Containers planted with annuals for seasonal color and interest
- A lamp post, trellis or arbor
- A new paver walkway
Corner plantings can extend the appearance of the house and help screen the side or backyard from view. If you'd like your house to appear wider, place plants beyond the corners of the house. Taller plants look best with taller homes.
Borders and beds complement and incorporate the home with the lawn, driveway and walkways. During renovation, foundation planting beds can be expanded further into existing lawns. Beds that are gentle and sweeping work better than right angles. Excessive curves give a busy look and are difficult to mow around. Add mulch and edging to make the area more attractive and reduce maintenance.
If you live in an area of the country that's susceptible to wildfire, pay careful attention to fire-resistant landscaping practices.
If you use wood mulch in your foundation beds and live in an area where termites are common, maintain a barrier of 6 to 12 inches between the mulch bed and wooden portions of the house. The barrier can be exposed soil, rubber mulch, crushed rock or marble chips.
Plant Placement
When planning where to install new plants, remember the problems discussed at the beginning of this article. The most important thing to remember when installing foundation plants is the spacing between the house and the plant.
Make sure you're placing plants where they'll look and perform their best. Avoid planting directly under the eaves. That area sees less rainfall due to the overhang, and plants too close to the house won't get the air circulation they need. In addition, the plantings can reduce your access for home maintenance. It's also a good idea to avoid planting too close to downspouts.
When planning plant groups, planting in odd numbers of three or five is more visually appealing than even numbers. Plant the groups in triangular patterns rather than straight lines.
Make sure plantings don't obstruct outdoor heating and air conditioning units. Planting too close interferes with air circulation and maintenance of the unit. If you have a pad-mounted electric transformer or other public utility structure on your property, check with the utility company before digging or planting.
Choosing Plants
When it's time to go shopping, there are plenty of plant choices. Before you go to the Garden Center, make sure you know the space you have available and the amount of sunlight the planting area receives. As you browse, read the plant tags. Pay attention to the mature size (height and width) and the spacing recommendations. The plant tag also provides sunlight and water requirements.
It's easy to plant small containerized shrubs too close to the house. It's usually a better idea to plant larger shrubs in these areas. They'll be a little more expensive and heavier, but you should need fewer.
Plants For the Front of the House
There are a variety of plants you could choose as landscaping bushes and shrubs for the front of the house. However, evergreens are an obvious choice of plants for the front of the house since they retain their color and form year-round. Evergreens include coniferous plants such as junipers and broadleaf types such as boxwoods. The many varieties and sizes of evergreens make them one of the best plants for the front of the house.
Deciduous shrubs are also excellent choices. Accenting the area with low-maintenance deciduous plants, such as hydrangeas and barberry shrubs, can provide features such as blooms, attractive bark or shape, fragrance or color contrast, especially in fall.
A specimen plant is chosen for one or more unique characteristics and is an important component of your planting design. It may be blooms, shape, fragrance or interesting bark. An ornamental tree such as dogwood, redbud, Japanese maple, crape myrtle, crab apple or one of many palms can be a quite dramatic addition. The effect can last day and night when the tree is accented with decorative lighting. Other options include topiary or fruit- or nut-bearing trees. Keep in mind that topiaries require regular pruning, and fruit trees will drop ripened fruit.
If you have limited space, look for dwarf varieties. They offer the perfect solution for many landscapes. They retain the desirable and recognizable traits of the full-size varieties but only need a fraction of the space.
To add color and variety, supplement the foundation beds with seasonal bulbs, ornamental grasses, trellised vines or annuals and perennials. Use containers to complement and add color.
Variables such as sunlight, water, feeding, soil pH and competition from other plants all affect growth rates. Especially consider water needs and availability when selecting plants.
Maintaining Your Foundation Plants
Prune to maintain neatness and health. Pruning also increases visibility and security near doors and windows. If you prefer low-maintenance options, avoid shrubs that require regular pruning. If you choose shrubs that look best when left alone to spread naturally, make sure that they're planted where they have room to grow.
Now might be a good time to consider landscaping for the side of the house. If you have a backyard where you entertain, for the side of the house you may want to consider creating a pathway to the backyard user pavers or steppingstones. A trellis or archway at the entrance provides an interesting focal point and also provides support for climbing vines.
Depending on your climate, some plants, such as dogwood and magnolia, are classified as shrubs but can actually reach small tree size.