Fragaria

This small group contains a few species of ornamental and edible plants, which may form clumps or runners. F. chiloensis and F. indica are two decorative, low-growing plants, which produce white flowers during the summer. F. ananassa is the species that produces the delicious, edible fruits we commonly know as the garden Strawberry. Strawberries are members of the Rose family. They are herbaceous perennials, although they tend to decline a bit faster in the Deep South, where they are usually treated as annuals. A well-maintained, disease-free crop can grow well for three to four years, after which the quality and yield decline. Many improvements have been made with the Strawberry. Hybrids have been developed that yield larger crops and produce larger berries, which last longer. Some of the wild berries are so delicate, that they should be eaten as soon as they are picked. Some cultivars developed for shipping can have odd flavor overtones. These are being replaced by cultivars that taste good even in the near ripe, firm stage seen in the grocery stores. It is important to choose a variety that is suited to your climate and resistant to the diseases common in your area. Strawberry hybrids vary in the timing and duration of their crops according to the number of hours of sunlight they receive at different times of the year. Cultivars are classified in one of three categories based on their response to daylength.

June-bearers: The typical Strawberry is a spring- or June-bearer because it produces its fruit in June, although in warmer climates, harvest may begin earlier. Because of the short days of fall, June-bearers form buds that blossom and fruit in the spring and produce one large crop over a period of about six weeks. If you want to have a large quantity of berries for jam-making, freezing, etc. at one time, June-bearers are for you. Don't plant early-season June-bearers if your region is subject to late frosts, which will injure the flowers.

Day-neutrals: Day-neutrals don't respond to daylength, rather they flower and fruit for about five months as long as the temperatures stay above 35°F and below 85°F and they receive proper care. Day-neutrals do best in the northern half of the US., from the mid-Atlantic to central California and in the higher, cooler elevations of the South. Day-neutrals tend to produce more berries in the spring and fall.

Ever-bearers: This type produces a crop in June and one in the fall. They form most of their flower buds during the long, summer days. Although Day-neutrals produce better quality fruit and higher yields, Ever-bearers are better for climates that have high temperatures.

Pot Cultivation

Soil: Strawberries need full sun and should be grown in deep, fertile, moisture retentive (but well-drained) soil, such as loam or sandy loam soil. They do best in slightly acidic soil (pH of 6.2) and will not tolerate pH extremes, such as less than 5.5 or more than 7.0. In heavy soil with poor drainage, Strawberries should be planted on raised beds. The beds should be built up 8 to 10 inches; this can be accomplished by taking soil from the aisles between the rows and adding organic material or buying good topsoil. Since Strawberries are shallow rooted, a site with access to water is important. Regular irrigation is necessary when you can't count on regular rainfall. To reduce the risk of verticillium wilt, do not plant in soil where tomatoes, potatoes, peppers, eggplant, blackberries, or raspberries have grown in the past three years. Verticillium wilt, nematodes and spider mites can be especially pesky in the lightweight soil of the South and warm West. Strawberry growers in these regions usually fumigate the soil every two years. The Strawberry beds must be kept weed-free because of the shallow root systems. Hand-pull the weeds or remove them by hoeing shallowly. The shallow roots should be disturbed as little as possible. Remove any soil that gets stuck in the crown.

Planting your Strawberries: In cold winter climates, Strawberries should be planted as early in the spring as possible (March or April in most of the US.). In warm-winter climates, plant from August through November. The plants will fruit in the winter months. In warm-winter climates, Day-neutrals can be planted in the fall or early spring. A cool, cloudy day is the best for planting sensitive transplants. When you purchase your plants, soak the roots in water for an hour or two (no more) and plant immediately. If you cannot plant right away, set the plants in moist sawdust in a plastic bag and store them in the coolest part of the refrigerator. If the roots are very long, trim them back about 4 inches. Remove and moldy or black roots before planting. Set plants 12 to 15 inches apart in rows that are 48 inches apart. Mulch the rows with black plastic, except in hot summer climates, where pine needles or straw should be used. Mulching increases productivity, decreases water use and helps to keep the fruit clean. Dig a hole deep enough for the roots to extend straight down. The soil should be level with the midpoint of the crown. Firm the soil and water thoroughly. Let the runners spread and root to form a solid matted row 15 to 18 inches wide, then clip off those growing longer. It is better for June-bearers if their flowers are removed during the first year. Your efforts will be rewarded the second year with a large crop of berries. The flowers of Day-neutrals and Ever-bearers should be removed for six weeks after planting; then let flowers form. Larger plants with higher yields will be obtained.

Watering: Make sure the plants are well watered for the first two weeks after planting. June- and Ever-bearers need 1 to 1 1/2 inches of water a week. When June-bearers are fruiting, they need 1 to 2 inches per week. On sandy soil or hot weather, they may need more. Soaker hoses or trickle irrigation is best for Strawberries because they keep water off the foliage, which helps prevent problems such as gray mold.

Fertilizer: The amount of fertilizer your plants need depends on the fertility of your soil and the health of your plants. Generally, June- and Ever-bearers should have 2lbs of 10-10-10 or 12-12-12 per 100 linear feet of row applied six weeks after transplanting and 2lbs per 100 linear feet of row in late August or early September. In the second and subsequent years, fertilizing should be done after harvest. Day-neutrals should be fed 2lbs of 10-10-10 per 100 feet of row every month, starting a month after planting until September. The second year, apply fertilizer beginning in May at the same rate and frequency. Fertilize your Strawberries when the foliage is dry, then water it in. Don't sprinkle fertilizer on the crowns.

Winter Protection: If you garden in a cold-winter region, cover the plants with about 6 inches of clean straw in the fall when the temperatures start falling to around 20°F and the plants are dormant. Early the following spring after the ground thaws and the risk of severe cold has passed, the mulch can be raked into the paths. Straw mulch shouldn't be used in areas with mild winter temps. and large quantities of rain, because the plants will begin growing and rot. In mild climates where some protection is needed, you can mulch with row covers of lightweight fabric instead of straw. This fabric, which can be purchased at nurseries or mail-ordered, allows light to penetrate producing higher yields. Be sure to remove the fabric in the spring before the plants flower to ensure good pollination.

Rejuvenating June-bearers: This can be done after their first productive year (the second year after planting) to maintain them for several more seasons. This isn't required but it helps them from becoming overcrowded and it increases the size of the berries. Mow the foliage to about three inches high just after harvest. Whether you use hedge clippers or a rotary mower, don't damage the plant's crown. Till the winter mulch you pulled off the plants in the spring into the space between the rows. Apply a 10-10-10 fertilizer at a rate of 5lbs per 100 feet of row. Then spread an inch of soil over the mowed plants. Irrigate as needed and remove excess runners as the form. In early September, add another 3lbs of 10-10-10.

Replanting: Strawberries will not produce well forever, so they'll need to be replanted. June-bearers become less productive after 2 or 3 fruiting years, Day-neutrals after 1 to 2 fruiting years, and Ever-bearers after 3 years in the ground. Remove all the plants and start over, if possible in a new location to prevent problems with soil-borne diseases. It is better to buy new plants rather than divide old ones.

Harvest: Berries ripen about 30 days after first bloom. For the best-tasting berry, pick them a day or two after the whole berry turns red. For making jam, harvest slightly under ripe berries. Pinch off the berries with your fingernails with the green caps on and about 1/2-inch of stem. Don't wash off the berries until you're ready to use them. Remove all berries, as overripe, rotting fruit will encourage diseases and insects.

Pests and Diseases: Here are a list of the most common problems: Verticillium Wilt; Red Stele; Gray Mold; Leaf Spots; Tarnished Plant Bug; Strawberry Bud Weevil; White Grubs; Spider Mites; Slugs and Snails. See the index on Pests and Diseases for more information.

Propagation

When ordering new plants, start early. Your supplier won't stock or send plants to you when it's too early or too late for your climate. Alpine Strawberries are divided every 2 to 3 years.

VARIETIES

Local, state and regional Strawberry trials are conducted by various governmental agencies and lists are published of the best modern varieties for home or commercial use. Make sure you choose a variety that is adapted to your climate. Consult your County Cooperative Extension or a strawberry nursery.

June-Bearers: Early Season - Chandler; Earliglow; Sequoia; Veestar. Early Midseason - Honeoye; Hood; Kent; Red Chief; Surecrop. Midseason - Allstar; Benton; Cardinal; Shuksan. Late Midseason - Glooscap; Jewel; Lateglow; Rainier; Sparkle; Tioga.

Day-Neutrals: Fern; Hecker; Selva; Tillikum; Tribute; Tristar.
Ever-Bearers: Fort Laramie; Ogallala; Ozark Beauty; Quinault.