By Bonnie Singleton
Strawberries have been popular fruit-bearing plants since ancient Roman times. They are perennials and fairly easy to grow, producing fruit for up to five years. The variety known as “(Fragaria x ananassa) Sequoia” or the “sequoia strawberry” is a favorite with gardeners, bearing large, robustly flavored berries in late spring and early summer.
Locate your strawberry plants in gardens, patio planters or hanging planters, as they do well in almost any spot. Planted outdoors, their lush dark green leaves will provide an attractive ground cover. If planted in pots, they can be relocated inside when the weather turns colder. The plants typically grow to a height of just under 6 inches (15 centimeters) and don’t need to be staked.
Strawberry plants are generally safe, but strawberries are a fairly common allergen. People who get allergic reactions when eating strawberries may also have a mild to moderate skin reaction from handling the plant at any point during its growth cycle, resulting in itching, hives and contact dermatitis. Note also that the berries will attract bees (as well as butterflies and birds); if you have an allergy to bee stings, this is something to keep in mind.
According to The Garden Helper plant encyclopedia (found online at http://www.thegardenhelper.com), strawberry plants are subject to fruit rot (botrytis), root rot (red stele) and fungus (verticillium wilt). Also be on the lookout for pests such as aphids and spiders, which will require dusting or spraying, and for slugs and snails, which can be controlled with copper barriers or special traps available at nurseries and garden-supply centers.
Consult your local nursery about which varieties of strawberry are best suited for your particular area and which pesticides and fungicides to use. Make sure to follow the instructions that come with whichever product you choose. If you’re planning on eating the berries, never use pesticides or fungicides on plants once the fruit has set, to avoid ingesting poison.
Consult a USDA plant hardiness map (such as the one found in the resources section below) to determine which growing zone you live in. Zone 1 is the coldest and zone 11 is the warmest. The Garden Helper suggests that in regions with severe winters (such as USDA zones 1 through 5), you should plant your strawberry plants in early spring (usually in March or April), as soon as the ground can be worked. If frost is predicted after planting, cover your plants. Old blankets or sheets will work; a spun bond material (Reemay is one brand) or a row cover can protect strawberry plantings at temperatures as low as 23 degrees Fahrenheit. Potted plants can simply be brought indoors.
In areas with milder winters, such as zones 6 through 11, plant your strawberries in the fall, from mid-September to mid-November; this will give you your first crop in the spring. Pick off flower buds during the first month or so after planting to allow the plants to get established and stronger.
There are two types of strawberries: June-bearing and everbearing. True to their name, June-bearing plants produce fruit in June. Everbearing plants (such as the sequoia) produce crops from the spring through the fall. Many gardeners plant both types to maximize strawberry production times.
If you purchased your strawberry plants, they will come in bareroot bundles with exposed roots. Separate the bundled plants, remove any dried leaves at their tops, and soak the roots in a bucket of warm water for an hour or so before planting. If the roots are long, you can trim them back to about 4 or 5 inches before planting.
Although most gardeners purchase strawberry plants, some choose to grow them from seed. If using seeds, plant them in a 1- to 2-inch layer of seed-starting mix, making sure to keep plenty of space between them. Cover with 1/8 inch of additional seed-starting mix, and keep them moist. The seeds will sprout in a few weeks; transplant the seedlings to regular soil when the sprouts have a third or fourth grouping of leaves.
Whether you are starting from seed or from a purchased plant, place your strawberry plants in a sunny location in acidic soil (a pH of 5.6 to 6.5). If you’re not sure of the pH level of your soil, you can purchase an inexpensive pH test kit at most nurseries or hardware stores. Set plants about 12 to 15 inches apart with the crown (top of the root) above the soil level and uppermost roots 1/4 inch below the soil level, spreading the roots out as you plant them. If the crowns are buried, they will rot, while plants set too high will dry out and die. Add a layer of mulch (sawdust, grass clippings or plastic sheeting) around the plants to prevent weeds from growing and to conserve moisture.
The gardening experts at bloomingbulb.com recommend mixing a complete plant food into the soil, then feeding again at mid-season. Water with an inch of water each week. Promote strong roots and plentiful berries by picking off the flowers for the first six weeks and trimming off any runners. Pull weeds by hand as needed, but avoid getting too close to the plants, since strawberry roots are shallow and easily damaged.
Strawberries grown in containers have the same needs as those planted in the ground. You can purchase specially designed strawberry pots, which come with rings of side holes; plants can be inserted in each hole.
Leave berries on the plant for a day or two after they reach peak red color before harvesting. The best way to know if they’re ripe is to complete a taste test; as the berries tend to bruise easily, pull them gently from the plant.
In cold-weather zones, after the plants have finished producing their last crop for the season, allow them to become acclimated to the cooler fall temperatures. Before the temperature drops below 20 degrees Fahrenheit, usually by late November, add 2 to 3 inches of protective mulch; use weed-free straw, chopped cornstalks, hay, corncobs or bark chips. Avoid using tree leaves and grass clippings, since these types of mulch can mat down and smother the plants during the winter.
Potted plants can be brought indoors.