GROWING RASPBERRIES
BEFORE YOU START
It is important that as you plan where you'll be planting your raspberries, you avoid soils where previous crops have included strawberries, brambles, potatoes, tomatoes, eggplants, or peppers. These crops may harbor soil pathogens, which will affect the health and performance of your new plants.
PLANTING
If the soil is not well-drained, raise the soil height of the planting rows or build twelve to eighteen inches (12–18") wide raised beds.
Plant as soon as possible in the spring, after your soil has warmed to 50°F. Planting too early, in cool, damp soil can delay development or cause roots to rot. Do not fertilize at planting. Planting at the correct depth is important. Your planting rows should be measured and maintained at no more than a twelve to eighteen inches (12–18") width.
When planting dormant, bare-root raspberry plants, use a hoe to make a two-inch deep trench the length of the bed. Lay the roots horizontally along the trench, two inches (2") deep. You may need to position some canes deeper than two inches (2") so that all roots on the cane are covered, still laying the length of the roots parallel to the soil surface at the two-inch (2") depth. Cover them immediately. The fine root system should not be allowed to dry out during the planting process, which can happen very quickly on a warm day. CAUTION: If set too deeply, they will not easily send up new canes from the root as they must.
Plant tissue culture plugs one-half to one inch deeper than the soil level of the plant.
TIPS
- We suggest soaking your raspberry plants for up to one to two (1–2) hours prior to planting, keeping the plants in the mail of water as you plant. Agri-gel and BioSafe Disease Control can be added to the water. Do not soak plants more than two (2) hours.
- Take care while planting to keep roots at two inches (2") depth to allow easy sucker development from the roots.
- Use of a product such as Agri-gel will help support the plants through short dry spells.
- Do not mulch beyond planting year, as it can impede new cane growth and cause root and crown rot.
CARING FOR RASPBERRY PLANTS
PLANTING YEAR
New growth may not appear for five to six (5–6) weeks. The cane portion of the plant may never lead out; expect most, if not all new growth to come from the roots. If you want to check for root development after six to seven (6–7) weeks, dig very gently two to three inches (2–3") away from the cane. Be careful not to damage delicate new sprouts that have not yet broken the soil surface. If the plants are not leafing out or sprouting new growth from the roots after seven to eight (8) weeks, call us.
IRRIGATION
Water thoroughly after planting and maintain good soil moisture until plants are well established. The plants should then receive one to two inches of rainfall or the equivalent each week throughout the season. Do not water every day – one to three times per week is sufficient.
FERTILIZATION
You may thoroughly incorporate a light amount of fertilizer at least two (2) weeks prior to planting. Do not fertilize when planting, wait until new transplants are well established. For optimum growth and production, home gardeners should apply ½ lb. – ¾ lb. of 10-10-10 fertilizer per 100 sq. ft. each spring and an additional one (1) lb. of 10-10-10 fertilizer per 100 sq. ft. in mid-summer. Do not fertilize after July 1, as late fertilization generates tender new growth which will be more susceptible to winter injury.
Commercial growers should use 500 lbs. of 10-10-10 per acre or make applications according to soil tests. Additional applications may be necessary according to weather and/or leaching conditions.
TISSUE CULTURE BRAMBLE PLANTS
PLANTING
- Cover the soil plug with ½”-1” of soil, using the same spacing as bare root plants.
- Fertilize TC plug plants the same as bare-rooted plants using ½ lb.-3/4 lb. of 10-10-10 per 100 sq. ft. incorporated at least two to three (2-3) weeks prior to planting or wait until plants are well established and then side-dress with 10-10-10 to maintain vigorous growth.
- Irrigate well after planting. Maintain good moisture levels until the plants are well established or for four to six weeks.
- Use care when applying herbicide on TC plants. We have had good results using four (4) lbs. per acre of Devrinol 50W. In our experience, other herbicides will damage these plants.
PRUNING
Pruning is an important part of the growing process that helps your raspberry plants prosper and maximize productivity. Raspberry plant roots live for many years, however, the shoots that grow from the roots live only up to two years. Removing old and weak shoots will encourage the growth of larger berries.
Primocane-Bearing Red and Yellow Raspberries
For fall production only, prune or mow all the canes to the ground in late winter/early spring, this is especially beneficial in colder areas. Be sure to cut the canes as closely as possible to the soil surface, leaving little or no stub above the ground. New, strong canes that emerge in the spring will bear an abundant fall crop.
To develop two crops, the planting must be pruned as summer-bearing varieties. When allowed to stand through winter, a second crop is produced early the following summer, lower on those over-wintered canes. After harvesting the summer crop, cut the over-wintered canes to the ground, leaving the new primocanes to produce the fall crop.
Floricane-Bearing Red Raspberries
These varieties carry one crop of berries during the summer on over-wintered canes. For the best yields, immediately after harvest, cut the canes that carried fruit as close to the ground as possible. Thin remaining new growth to six to eight (6–8) strong, healthy canes per running foot of row. In late fall, cut canes down to four-and-a- half to five feet (4.5’–5’) to manage the picking height.
Primocane-Bearing (Fall-Bearing/Everbearing) Black Raspberries
Primocanes require pruning during the growing season, called tipping. Tipping makes plant management easier and increases yield potential. When new primocanes reach 3 feet, tip the top 1 inch of the primocanes to encourage the cane to grow lower lateral branches. This process increases the places where the plant can produce fruit.
Pruning later in the season decreases the plant's time to develop branches. Failure to prune the primocanes will allow earlier ripening, but the canes will become tall and arching and develop fewer berries.
Floricane-Bearing (Summer-Bearing) Black and Purple Raspberries
Black and purple raspberries break buds from their crown or base and send out few, if any, suckers. Prune plants to 4–6 canes per hill.
Primocanes require pruning during the growing season, called tipping. Tipping makes plant management easier and increases yield potential. In midsummer (typically through July and August), when the first-year canes reach 5–6 feet in height, tip the first-year canes by pinching off the top 2 inches. This practice encourages fruiting lateral branches to break from the main cane and keeps plant height in check.
In the late fall, prune laterals to 6–8 inches. Pinching back laterals can help increase berry size and increase winter hardiness.
REMINDER:
Old canes should be cut as close to the ground as possible to force new buds to break below the soil surface. Cane stubs above ground can be entry sites for insects and disease pathogens.
RASPBERRY PLANTS QUICK REFERENCE
Spacing
- Eighteen to twenty-four inches (18–24") for red and yellow raspberries; twenty to twenty-four inches (20–24") for black raspberries.
- Recommend eight to twelve feet (8–12') between rows depending on the machinery.
Irrigation
- Soak in water using Agri-gel for one to two hours before planting (except for tissue culture plugs).
- Water thoroughly after planting.
- One to two inches of rainfall or equivalent per week.
Fertilization
- Before planting add ½–¾ pounds of 10–10–10 per 100 square feet.
- Commercial growers should use 500 pounds per acre.
- An additional one pound of 10–10–10 per 100 square feet can be applied in July or August and in early spring in the following years.
- pH: 6.0–6.5.
Weed Control
- Regular cultivation is necessary during the growing season.
- Roots are shallow—don’t cultivate more than an inch deep.
- Mulching during establishments can help control weeds.
- Contact a local extension for chemical recommendations.
Trellis
- We suggest plants are supported by a T-trellis, as pictured below.