Strawberries planted in the field need moderate to high amounts of water. Strawberries are relatively shallow rooted, with almost all their roots in the top 8" of soil, so deep irrigation is not necessary; instead, give them moderate amounts of water on a regular basis--and do not overwater.
If possible, use a soaker hose or a drip irrigation system to water strawberries. That way you will prevent the strawberry foliage from getting wet and thus make the plants less susceptible to foliar disease.
You should mulch your strawberry bed (Image 1) to conserve moisture, to help prevent the spread of disease, to help suppress weeds and to keep berries clean and soil-free. You can use black plastic mulch or organic mulch such pine straw or regular straw.
Some strawberries growers say that if the bed was prepared properly and well fertilized before the strawberries were planted, no additional fertilizer is necessary during the growing season. Other strawberry growers prefer to fertilize regularly, with either liquid fertilizers or with granular 10-10-10, every few weeks during the first half of the growing season.
If you apply granular fertilizer to your strawberry patch, apply when the foliage is dry and avoid getting it on the leaves (Image 2). If the fertilizer does get on the leaves, brush it off to prevent leaf burn (Image 3).
As strawberries grow, they send out runners. If you're treating strawberries as annuals, you typically pinch off the runners so that the plants can concentrate their energy on fruit development. If you're treating strawberries as perennials, however, you can let the runners grow and develop into daughter plants. About every 12" along the length of the runner a baby, or daughter, plant will develop.
Strawberry plants will flower as soon as they get established in the landscape. For strawberries being treated as annuals, pick off the flowers for the first month so the plant has time to grow strong and sturdy. After that let the flowers develop into berries. For strawberries being treated as perennials, growers pick the flowers off for the first year, which delays the first harvest until the second year.
Strawberries need protection when temperatures drop into the teens. You can use 4"-5"-thick layers of organic mulches such as hay or pine straw, or you can use fabric grow covers to help insulate the plants.
Some varieties of strawberries are better able than others to withstand really cold temperatures, so it's a good idea to check which varieties are tried and true in your climate. Your local cooperative extension service and your local nurseries are usually good sources of this kind of information.
Anthracnose (Image 1) is a fungal disease that's especially common in hot, humid climates. The fungus causes brown, sunken spots on the fruit and often causes the plants to die. The frequent occurrence of this disease in hot climates is why so many people prefer to treat strawberries as annuals and to start each year with new, certified disease-free plants.
Other diseases include crown rot, light blight, fruit rot and leaf spot. The best line of attack is prevention: keeping the plants stress-free by proper watering; not working in the field when the plants are wet (because diseases spread more easily among wet plants); keeping weed competition down; and choosing the right plants for your climate.
If you decided to use pesticides, be sure to start with the least toxic pesticide possible, and follow all label directions. Strawberries are also sometimes bothered by pests such as aphids. Again, choose the least toxic approach to controlling pests. One option is to introduce beneficial insects, such as ladybugs (Image 2), to your garden to control pests.
Birds love ripe berries (Image 1). To keep birds from eating all your berries, it's a good idea to cover the plants with bird netting as soon as the berries begin to ripen. The netting is easy to lift off for picking the berries, and it's easy to replace. Be sure to weight down the netting with stones, boards or rocks so it doesn't fly away. And don't leave any gaps where the birds can hop in underneath the netting. A realistic-looking owl on a post will help scare pesky birds away from your berries (Image 2).
Keeping weeds out of the strawberry patch is important: if weeds are allowed to take over your berry patch, you'll have constant disease problems and will have few, if any, berries. Mulching is one way to suppress weeds: weed seeds can't germinate unless they have sunlight, and mulch blocks the light. If you do get weeds, hoe or hand-weed as necessary, but don't dig too deeply and don't disturb the plants' roots.