Garden Variety: Strawberry yields forever

The taste of a vine-ripened strawberry is like the first taste of summer to those who grow them and those who relish fresh local fruit.

Their sweetness and flavor is well worth the labor to produce them, yet I often hear reports from gardeners who have limited success. The secret, I suspect, is that strawberry plants need care right now, as the picking season ends.

Strawberry plants spend the summer storing away energy to survive the winter and produce fruit the following year. They also set the buds that will be next year’s fruit in the fall. This means that if plants are dry and stressed in July-September, next year’s crop will be poor regardless of what the following spring brings.

If you’re looking to grow a successful strawberry crop next year, begin making preparations now.

The exception to this rule are everbearing strawberries, which produce (limited) fruit throughout the season. Everbearing strawberries should be cared for in the same manner as June-bearing strawberries, however.

Proper care for strawberry plants depends on their age. In the first year, focus on establishment. Plants need about 1 inch of water per week. Use drip irrigation or soaker hoses to provide supplemental moisture during hot, dry periods and divide the application into two per week in the hottest parts of summer.

Too much moisture is also conducive to diseases and stress, so if strawberries are planted in an area with poor drainage, they may need to be moved. Soil drainage is best improved by mixing in compost. Weed control in the strawberry patch is crucial over the summer months to reduce competition for water, light and nutrients.

First-year strawberries will benefit from fertilizer applied in early-to-mid-August. Use a 10-10-10 or 12-12-12 fertilizer (or something with similar numbers) and apply about 3/4 to 1 pound of fertilizer per 25 feet of row.

There are conventional and organic fertilizers available in these formulations. Look closely at the bag or box to find the numbers — all fertilizer sold in Kansas is marked this way. The three numbers represent the ratio of nitrogen to phosphorus to potassium. Water the fertilizer into the soil immediately after application.

For second-year and older plantings, go through the patch after the last berries are picked. Thin plants until the remainder are about 4 to 6 inches apart. This will improve vigor by reducing competition. Add an inch of soil to the bed to completely cover the crown of the plant and allow for new root formation. Fertilize at the same rate as first-year strawberries.

Many guides also recommend mowing or clipping the leaves from the plants at this time to reduce the buildup of foliar disease. Plants will produce new leaves within a few weeks.

Everbearing varieties will benefit from an additional early spring fertilizer application at the same rate as above and should be mulched over the summer to keep fruit from laying on the soil surface.

Proper watering and weed control over the summer is equally important in established plantings as in first-year plantings. Just remember, the plants will reward your work next May and June.

— Jennifer Smith is a former horticulture extension agent for K-State Research and Extension and horticulturist for Lawrence Parks and Recreation. She is the host of “The Garden Show” and has been a gardener since childhood. Send your gardening questions and feedback to checkout@ljworld.com.