What is a Perennial?
A perennial plant or simply perennial is a plant that lives for more than two years. Some perennials grow for decades!
Just a few from Mary's Heirloom Seeds,
"It's as close to zero-work gardening as you can get," says Eric Toensmeier, author of Perennial Vegetables. "Our perennial vegetable beds planted 11 years ago still bear food, and all we do is add compost and mulch once a year."
From The Self Sufficient Homeacre, "Are you interested in growing your own healthy food, becoming more self reliant, saving money, and planning for the future? Then you should be interested in perennial crops. Your initial investment of time and money will reward you for years to come. Prepare your perennial beds properly, water and weed your plants, top dress with compost, and you will harvest fresh food for your table year after year."
Grow artichoke (Cynara scolymus) in full sun and moist, well-drained soil. Artichokes require ample, consistent moisture for best growth. They survive drought but don't produce as well in dry conditions.
Plant 24-36 inches apart in rows about 36 inches apart. Amend the soil prior to planting with 2 inches of compost. Fertilize monthly with a high-nitrogen fertilizer. When growing artichoke as a perennial, amend the soil around plants each spring with a 1- to 2-inch layer of compost.
Artichoke plants should produce for about 3 - 5 years. At that time, you should notice side shoots at the base of the plant. You can lift, divide and replant the new shoots.
This hardy crop lasts for decades in the garden and is one of the first vegetables that can be harvested in spring. Plant asparagus (Asparagus officinalis) in full sun and moist, well-drained soil. Mix a 2-inch-thick layer of compost into the planting site. Because asparagus is long-lived, it's important to adequately prepare the soil before planting.
In the second year after planting, harvest for only two weeks. By the third year, harvest for the usual five to eight weeks. Start harvesting when the spears are 1/2 inch in diameter
This sharp-flavor vegetable is technically a hardy biennial, meaning it grows for two years. It is a type of chicory and is related to Belgian endive. Dark red leaves with white veins form into a tightly clumped head that resembles cabbage or romaine lettuce. Grow radicchio (Cichorium intybus) in fertile, well-drained soil in full sun. Sow seeds in spring or autumn, then harvest the inner heads in late fall when they are firm and have the deepest color of white and red, leaving the roots in the ground to produce another crop.
Though many people treat it like a fruit, rhubarb (Rheum rhabarbarum) is actually a hardy perennial vegetable (because you eat the stems, not the plant's fruits).
Plant rhubarb in full sun and moist, well-drained soil. Locate it where it won't be disturbed because it will be productive for many years.
Apply a balanced fertilizer in early spring. After harvest, spread a 2-inch layer of compost around plants. When the stalks become thin, usually after six to eight years, dig and divide the plant in spring or fall. Leave first-year plants unharvested. By the third year, harvest all stalks larger than 1 inch wide for as long as eight weeks. Use only the stems; the leaves contain oxalic acid and are poisonous.
Some eggplants will continue to grow for up to 3 years. This takes propper care and the right conditions. The greatest bloom is usually observed in the indeterminate, with fruit and seed production starting in the year round and continuing until year round. Leaves are retained year to year. The Eggplant has a short life span relative to most other plant species and a rapid growth rate. At maturity, the typical Eggplant will reach up to 4 feet high.
To grow sorrel, sow seeds directly in the garden in full sun and average soil 6-8 inches apart in rows 2 feet apart. Established plants may be divided.
Certain varieties of pepper can grow for several years. Perennial Peppers include:
Scotch Bonnet (special order)
The young leaves and stems of this 6-foot-tall perennial are an excellent substitute for celery in springtime soups. The seeds and roots are also edible, and the umbel flowers attract beneficial insects. Lovage thrives in average garden soil, in sun or partial shade.
These are different than herb varieties that self-seed or re-seed such as Basil and Cilantro.
I've seen them grow over 5 feet tall and over 8 years old. Rosemary is an excellent choice for a "plant it once" kinda garden!
Additional Perennial Herbs include:
If you are going to have both perennials and annuals in your garden, it's wise to keep them in separate areas to make planting annuals easier, as well as cleaning up at the end of the growing season.
Be warned that some perennials can be so hardy that they are actually spreading and invasive. Everbearing strawberry plants and blackberry vines are known to spread and spread. You may want to plant them in containers to control them.