Floricane/Summer Bearing Red Raspberry Production –
The Ins and Outs
Brambles are a high value crop much in demand. Here we focus on on summer bearing red raspberries: an excellent complement to strawberries. Varieties typically ripen after strawberries, but before significant SWD pressure.
• Preparations for red raspberry plantings should begin at least one year in advance. We advise taking soil samples to get a read on your pH, % organic matter and overall fertility to make any necessary changes the year before planting.
• We recommend a pH in the 6.5 – 6.8 range with a minimum 2-3% organic matter. A nutritionally healthy planting in a well-drained soil with exposure to air movement is less susceptible to damage from pests and frosts.
• Raspberries require good internal soil drainage to grow and do best on a well-drained sandy loam. Wet soils restrict root growth and respiration, resulting in weak growth and reduced yields.
• Planting on raised beds is highly recommended to improve soil drainage in the rooting zone, particularly on heavier soils. Selecting a site with a gentle slope (3-4%) and good air drainage will also promote faster drying of foliage, flowers and fruit which will reduce the duration and frequency of disease infection periods Recommended plant spacing is 18 – 24 inches in the row and 10-12 feet between rows.
• Drip irrigation is an essential component to successful raspberry production. Plants generally require 1 to 2 inches of water per week during the growing season and 2 to 3 inches per week during harvest. We suggest having your local irrigation sales company review your field layout for the best recommendations for your situation.
Choosing a variety
Picking the appropriate varieties for your operation is one of the most important decisions a grower can make. In northern areas, winter-hardiness is a key factor in choosing a variety. On the flipside, in zones 7 & 8, care should be taken in variety selection to ensure the fruit can handle intense summer heat. The following is summary of key summer bearing varieties – additional information on these and other varieties can be found on our website or in our catalog.
PRELUDE - Well accepted early variety. Growers like the early season primocane crop combined with good berry quality. In some locations, Prelude produces a primocane/fall crop.
NOVA - In the trifecta of summer bearing key varieties, a very consistent second variety in ripening time. Nova is dependable for winter hardiness, overall plant vigor and being highly productive.
KILLARNEY - In similar ripening window as Nova, some growers prefer this variety for its performance, better fruit quality, and flavor in their conditions.
AAC EDEN - Tested as K06-2, AAC EDEN was released by Andrew Jamieson at Kentville, Nova Scotia. Mid-season, summerbearing floricane. A cross between Glen Ample and K93-11, the strong canes are spineless and demonstrate moderate winter hardiness. The conical fruit are large, firm, light to medium in color with excellent flavor.
ENCORE - Best alternative for a late floricane bearing raspberry. Encore is not the most productive, but fruit quality is excellent. Encore is also the best variety to connect to the primocane/ fall bearing season.
Planting & Fertilization
Avoid planting raspberries in soils where previous crops have included brambles, strawberries, potatoes, tomatoes, eggplant or peppers. Destroy all wild raspberries and other brambles within 500 to 1,000 feet of your planting site. We recommend planting early in the spring when soil temperatures are in the 45 – 50-degree range. With a bare root red raspberry planting, tips to remember: • Suggest soaking the plants for up to 2 hours before planting, taking care to keep the roots moist during the planting process.
• Do not plant too deep. We recommend digging a trench approximately 3-4” deep, laying the roots horizontally along the trench making sure roots are 1 – 1 ½” below the soil surface. Keeping roots at this depth and not too deep allows for easier sucker development from the roots.
• Consider using a product such as Agri-gel TM to help support plants through short dry spells.
• Consider the use of plastic as a weed barrier on the planting year. Contact us for details. Do not fertilize at planting. Earlier in this article, we recommend a soil sample the previous year to determine nutritional needs. If needed, once plants are established,
apply 20-35 pounds actual nitrogen per acre based on soil type. Higher levels of actual nitrogen may be recommended in subsequent years based on soil tests.
Not necessarily new to some growers, high tunnel raspberry production has been a topic at many of the winter meetings, with discussion of variety selection and overall production. We have had excellent success in using high tunnels in our own bramble production, including summer bearing red raspberries, and welcome any questions you might have.
Trellising & Pruning
We recommend all brambles, including red raspberries, be supported by trellis. A trellis keeps canes upright and fruit off the ground, makes picking much easier, and maintains good aeration throughout the planting which helps with disease control. We have been successful using a T-bar trellis which supports 2 wires 12” apart at 3’ to 4’ above the ground. Some taller-growing varieties, such as Nova and Prelude, might benefit from a T-trellis with two T-bars – one at 3’ and one at 4’. Growers of Summer-Bearing varieties find it’s helpful to attach first year canes to the wires on one side of the trellis, alternating this with each year’s new canes. Summer-Bearing (Floricane-Bearing) red raspberry varieties carry one crop of berries during the summer on over-wintered canes. For best yields, immediately after harvest, cut the canes that carried fruit as close to the ground as possible and remove from the field. Thin remaining new growth to 6-8 strong, healthy canes per running foot of row.
Good weed control during the first year is essential. Raspberry plants are sensitive to most herbicides during the first few months after planting. Research from Cornell has shown that applying a clean straw mulch (4 inches deep) to newly plant raspberries provides good weed control. On heavy soils mulch should be used only in the first year since straw mulch over a prolonged period can encourage the development of root rots. We do not recommend bark mulch or any other mulch material besides straw. Like any crop, a variety of pests need to be managed to maximize yields, fruit quality, and extend the life of your planting. Based on grower experience, besides Spotted Wing Drosophila which impact later ripening summer raspberries, growers should be concerned with:
• Phytophthora Root Rot
• Botrytis Fruit Rot (Grey Mold)
• Aphids • Yellow (Late or Fall) Rust
Please review our Spring 2018 and other past newsletters on our website or contact your local cooperative extension office for specifics on possible controls.