Raspberry

The most important thing to understand about raspberries before you plant them is that there are two types, and they are managed completely differently. Summer-bearing raspberries (also called floricanes) produce fruit on two-year-old canes — wood that grew last year. Fall-bearing raspberries (also called primocanes) produce fruit at the top of canes that grew this year. If you don't know which type you have and you prune them the same way, you can easily cut off all next year's fruit, or leave a thicket of spent wood that crowds out the productive canes.

Plant bare-root canes in early spring, as soon as the soil can be worked — several weeks before your last frost. Raspberries establish better in cool conditions than in warm. Set canes 24 inches apart, in rows 6 to 8 feet apart to allow for spreading. Dig a generous hole, spread the roots, and cover so the crown is just at or slightly below the soil surface. Water in well. Cut the cane back to about 6 inches at planting — this concentrates energy into root establishment rather than the existing cane, which will die back anyway.

Summer-bearing varieties fruit only in early summer. Each cane lives two years: in year one (primocane) it grows vegetatively; in year two (floricane) it flowers, fruits, and then dies. After summer harvest, cut the floricanes (the ones that fruited) to the ground and remove them. Leave the new-growth primocanes — they'll be next year's fruiting canes. Thin those to four or five per plant, stake them, and they'll carry next summer's crop. Fall-bearing (primocane) varieties are more flexible: you can mow every cane to the ground in late winter and get one fall crop each year, or leave the lower half of fruited canes to get a small early-summer crop in addition to the fall flush.

Verticillium wilt is the disease that ends most home raspberry plantings prematurely. The plant wilts from the top down despite adequate water; canes die and the root crown eventually fails. It's caused by a soil-borne fungus that can live in the soil for decades and is most commonly introduced via infected plant material. Never plant raspberries where tomatoes, potatoes, eggplant, or strawberries grew recently — those crops share the same pathogen. And buy certified disease-free stock; cheap bare-root canes from unknown sources are a common vector.

Overwintering is generally straightforward for northern varieties in their rated zones, but cane desiccation can occur in exposed sites in zones 3 and 4. In the fall, after canes are tied and the foliage has dropped, some growers in very cold climates bend the canes over and pin them to the ground, then mulch over them with straw. The insulating snow cover does most of the work in snowy climates; the mulch serves where snow cover is unreliable. Uncover and tie canes back up in early spring before growth begins.

Raspberries spread by suckering — new canes emerge from the roots beyond the row. These can be dug and moved to fill gaps, or cut off at the soil line if they're coming up in a path or too far from the row. Without annual management of suckers, a raspberry planting can spread well beyond its intended bed within a few seasons. A defined row, managed with a spade or hoe every spring, stays productive and accessible for much longer than one allowed to naturalize.