Raspberries are a favorite item at the grocery store for many people. In the wild, they can be found growing in roadside ditches or along tree lines. They are also a favorite plant in the garden. They can be grown in abundance with the right knowledge and conditions. Paul Read, professor of Agronomy and Horticulture at the University of Nebraska-Lincoln, specializes in viticulture.
Different raspberry plants, he says, may produce red, black, or purple fruits in the fall. The plant is perennial. The raspberries themselves grow where once there were flowers and pull free from the stalk.
Black raspberries may bear a resemblance to blackberries, but raspberries are hollow where the berry connects to the stalk. Blackberries have a white core where the fruit connects to the stalk.
Read says it is important to know the distinction between types of raspberry plants. In Nebraska, people can grow red, black, and lesser-known purple and golden raspberries—and there are fundamentally different types of plants.
The standard type of raspberry plant is a floricane, which produces flowers and fruit on the second year’s growth, Read says. The ever-bearing, or primocane, plant produces at the end of the first year’s growth. This type of plant is sought after by commercial and home growers because it fruits sooner. With an ever-bearing plant, one may be picking quite a few berries by late August or early September.
“It’s nice to get fruit the first year,” Read says.
Standard raspberry types, and notable black raspberries, have barbs on their stalks, although thornless varieties are becoming more available. Thorny plants are more cold-tolerant, says Read; but he notes that many thornless varieties do well in Nebraska’s climate. “The best thorny types are miserable to harvest,” he adds, laughing.
Although raspberries may be found growing in various conditions in the wild, in order to optimize their production, the home gardener should follow a few simple rules. Raspberries should be planted in full sun, Read says, not shade.
“They [raspberry plants] should get 6-8 hours of full sun [per day],” Read advises.
He says there is some advantage to north-south row orientation because the southern slopes receive more sun in the northern hemisphere.
The casual home gardener should place raspberry plants 1.5 feet apart in their row, and rows should be placed 3-4 feet apart, Read says. He notes that more space may be optimal but understands that may be unrealistic to homeowners.
Read says it is generally useful to mulch raspberry plants in order to control weeds. Many types of mulch will work. Black landscaping fabric is particularly clean and easy to use. Organic mulch tends to cool the ground, which is good in the heat of the summer. Plastic mulch tends to warm the soil, which is good in the spring and can be good in the fall.
Read recommends supporting the raspberry plants using wires that are attached to posts, planted in the ground every few feet. The plants are then trained up the wires.
At the end of the year, cut down the stalks, Read says. It minimizes the risk of overwintering pests and diseases.
With this knowledge and a little luck, a home gardener can have raspberries this fall and next.
Visit extension.unl.edu for more information on gardening raspberries and other plants.
This article was printed in the June 2019 edition of OmahaHome. To receive the magazine, click here to subscribe.