Perennial Fruits and Vegetables for the Edible Landscape

When people get interested in food gardening, they tend to stick with traditional annual vegetable crops, such as tomatoes, beans and lettuce. But there are many other terrific food crops that yield a bountiful harvest with far less effort. Perennial fruits and vegetables, such as asparagus, blueberries and rhubarb, get planted once and then go on to produce food for several years and in some cases, a lifetime!

Some of these plants, such as asparagus and strawberries, work best when planted in standard beds, in or around the vegetable garden. Others, including blueberries and rhubarb, are shrub-like and can be integrated into your landscape along with other shrubs and trees.

Perennial food crops, like almost all fruiting plants, require at least six hours of sunshine and appropriate amounts of water throughout the growing season. Some plants are pickier than others about things like soil pH, drought and winter cold. An easy way to find out what perennial food crops might be successful in your area, is to visit a local farm stand or farmers market. If they’re growing something successfully, chances are good that it’s worth a try at home! You can also contact your state’s Master Gardener Hotline through the state Cooperative Extension office.

Almost all plants will perform their best in fertile, well-drained soil. most state Cooperative Extension offices offer free or low-cost soil tests that will let you know if you have adequate organic matter, minerals and if the pH of your soil (its acidity) is appropriate for the types of plants you want to grow.

Because perennial food crops get planted just once, it’s valuable to invest some time preparing the soil to ensure long-term health. Work in compost as well as an all-purpose, organic fertilizer that will provide nitrogen, phosphorus, potassium and trace minerals.

If your soil is poor, consider planting your perennial food crops in a raised bed. This allows you to customize the soil mix, and will keep tasks, such as weeding and pruning, to a minimum.

Most fruits and vegetables require about an inch of water per week. If you expect that you’ll need to be watering frequently, consider investing in an automatic timer and a drip irrigation system. This will get the water directly to the plants and minimize waste. Mulching plants with several inches of organic matter (straw, fall leaves, compost or shredded newspaper, is an easy way to suppress weeds while also preventing moisture loss from the soil surface. Organic mulches, such as the ones listed above, will gradually break down, adding additional organic matter and valuable nutrients to the soil.

Asparagus: Modern cultivars in the 'Jersey' series produce all-male plants, which will give you much higher yields than older varieties from the 'Washington' series. Asparagus roots get planted relatively deep, so loosen the soil to a depth of 12-inches or more, adding compost and granular organic fertilizer. A well-prepared and well-tended asparagus bed can be productive for 30 years or more.

Each asparagus “crown” is comprised of four to eight roots that are joined at a central point. For each crown, dig a hole about 12-inches deep and 16-inches in diameter. Mound up the soil in the middle, set the crown on top and then spread out the roots. The top of the crown should be about 6" below the soil surface. Fill in the hole and water well. Asparagus does not compete well with weeds, so keep the area mulched and weeded. Harvesting can usually begin the second or third year after planting. Asparagus is hardy to at least minus 30 degrees F.

Blueberries: Blueberries must be grown in acidic soil that has a pH level of 4.0-5.5. If the pH level of the soil is more alkaline than this, the plants are not able to properly absorb the nutrients they need to sustain healthy growth and good fruit production. Blueberries are shallow-rooted and prefer a well-drained soil with a high organic content. Unless the soil in your yard is naturally very acidic, you’ll need to apply an acidifying agent at least once each year. This may be in the form of pine needle mulch, agricultural sulfur or a fertilizer formulated for acid-loving plants (azaleas, hollies, etc.) Hardy to minus 30 degrees F.

Of all plants considered for edible landscaping, blueberries are among the most attractive — especially the highbush types (Vaccinium corymbosum). These shrubs have distinctive gray bark and are covered with white, lantern-like flowers in spring. In addition, the plants put on a beautiful show in the fall as the leaves turn a mixture of orange, red and yellow. Highbush blueberries can be used to form a hedge or add variety to a shrub border. Keep in mind that these shrubs are sure to attact wildlife. If you want berries for yourself, be sure to have some bird netting on hand when the fruit begins to ripen. Learn more about growing blueberries in the Vegetable Encyclopedia.

Rhubarb: Rhubarb is grown for its juicy, super-tart stalks. It does not require full sun — four hours is usually sufficient. A rhubarb plant that is well cared for can produce for 30 years or more, so think carefully about where you locate it. When preparing the soil, dig in a bucket of compost and a cup of organic fertilizer for each plant. For best results, keep the area well mulched to maintain consistent soil moisture. Remove flower stalks as they appear to keep the plant producing. Top-dress around the plant with compost each spring. Learn more about growing rhubarb in the Vegetable Encyclopedia.

Raspberries: Raspberries multiply by sending their roots in all directions, so this is a good plant to contain in a raised bed. Plant in full sun, in well-drained soil that has been amended with compost and organic fertilizer. Good air circulation is important for maintaining healthy plants and quality berries. Summer-bearing raspberries produce fruit on the prior year’s canes. Each fall, canes that bore fruit should be pruned to the ground. Weak canes should also be removed, leaving only six or eight strong canes per plant. Ever-bearing raspberries produce fruit on the prior-year canes as well as current-year canes. For a continuous crop of berries from summer through fall, remove all spent canes in fall, and leave only a few young canes. Hardy to minus 30 F. Learn more about growing raspberries in the Vegetable Encyclopedia.

Strawberries: Standard strawberry varieties produce one large crop of berries in early summer. Everbearing strawberries produce a similar size crop, but over a several-month period. Plant strawberries in full sun, in rich, well-drained soil that has been amended with compost and organic fertilizer. Strawberries should be mulched during the growing season with shredded leaves or straw to keep the soil moist and the berries clean and dry. Plants reproduce by sending out runners with smaller "daughter" plants. Thin to avoid overcrowding, keeping only the healthiest plants. In cold climates, strawberry plants benefit from a winter mulch of straw or leaves. Hardy to minus 30 degrees F. Learn more about growing strawberries in the Vegetable Encyclopedia.