Question & Answers
about Raspberry Farming

Substrate culture

• • Reasons for growing raspberries in growing media:
    • Land scarcity
    • Soil exhaustion
    • Timely cultivation
    • Better fruit quality
    • Weed suppression
    • Achieving higher yields
  • Recommended primarily for long-cane plants
    • Use with potted long-cane plants
    • Directly in growing medium troughs
  • Regular water and nutrient supply
    • Continuous drip irrigation recommended
    • Avoid waterlogging at all costs
    • Flat or only slightly sloped surfaces are ideal for irrigation
  • Specialized consultation regarding irrigation, fertilization, and crop management is absolutely essential for growing in growing medium

Term culture

This method of managing harvest timing is particularly interesting for those who want to plan a specific harvest period with consistently high fruit quality. This cultivation method is made possible by using chilled raspberry canes.

Depending on the weather, it takes about 10–12 weeks from planting to harvest. The plants are set out at intervals to allow for a long harvest period.

Summer Raspberries

Option I: One-Year Cultivation

For one-year cultivation, the canes are trained upward in the year of planting so they can be harvested the following year. It is important that the canes reach their full length already in the first year. In the harvest year, all young canes are removed so that the plant can focus its energy on the current crop. After the harvest period is complete, the plants are uprooted, and new plants are then planted. Annual raspberry cultivation is a good way to counteract the aging of raspberry stands.

Option II: Multi-Year Cultivation

In the first year of planting, young canes are grown for the following year, so there is no harvest in the first year. Young canes from the existing plants are also cultivated in the following harvest year. This is done simultaneously during the harvest period of the old canes. The goal of this process is to produce a new harvest the following year. This cycle can be repeated for several years. The old canes should be removed after harvest so that the young canes can develop for the next year.

Fall Raspberries

Option I: One Harvest Per Year

These raspberry varieties bear fruit on one-year-old wood. The young canes of fall raspberries are grown in the spring and produce the first harvest as early as the fall. Before winter dormancy, all canes are cut back to ground level, with the goal of achieving a fall harvest the following year.

Option II: Two Harvests a Year

With this cultivation method, young canes are trained in the spring and produce the first harvest as early as the fall. After the harvest, the canes are pruned below the last flower cluster. These canes overwinter in the field and can be harvested again the following spring. The harvest can usually be carried out about 2 weeks before the summer raspberries. At the same time as this harvest, new young canes are trained, which will be ready to bear fruit again by the fall of the same year. After the third harvest, replanting the raspberries is recommended. For this cultivation method, growing in substrate, under rain covers, or in a tunnel is also recommended.

Plugplants

When cultivating plugplants, cuttings are planted in growing medium and allowed to root; planting trays are usually used for this purpose. Plugplants are delivered with a growing medium ball. This type of plant can be used, for example, to cultivate long-cane plants. Potted green plants are also well-suited for growing in open ground. Weed growth can be effectively controlled by using raised beds or plastic mulch. For the best possible results and to protect them from the wind, they are stabilized with wire, a bamboo stake, or twine. Side shoots can also be secured with netting or twine.

· Planting possible starting in May—very important: only after the last frost

· Optimal water and nutrient supply from the start

· Optimal cane length in the first year: 160–180 cm

· Recommended planting spacing: six canes per meter

Long Canes

Once the canes have reached the desired length and the roots are well-developed, they are stored in a cold storage facility as soon as dormancy sets in, similar to “Frigopflanzen.” The following year, they are ready for cultivation, for example, in a plastic tunnel or under rain covers. Long, pre-grown raspberry canes with buds that are approximately 1.60–2.00 m long are referred to as “long canes.” Thanks to the existing buds, a first harvest is possible as early as the year of planting. Commercially available potted long-cane plants are supplied in a 1.8-liter pot (container) and usually contain two raspberry canes. To stabilize them, they are trained on a trellis in the year of planting.

· Harvest begins 9–12 weeks after setting up the trellis/planting

· Timed harvest possible through planned planting

· Recommended planting density of six canes per meter (= three pots, each with two canes)

· Protected cultivation in a plastic tunnel or under rain covers is recommended

· Long Canes are produced only to order—orders must be placed by early May at the latest for the following year

Summer Raspberries

Standard Hedge, Wire Frame

In this system, stakes are driven into the ground, and a double wire is stretched between them at three points. The raspberry canes are then positioned between the wires, providing them with more stable support. For varieties with longer fruit clusters, it is recommended to install additional support wires or wire mesh on the sides.

Fall Raspberries

Wire trellis

This training system is mainly used for fall raspberries. Here, a simple wire trellis mounted on stakes serves as support, allowing the canes to grow upward through it. It should not be wider than about 40–50 cm, otherwise the plants will become too dense.

When choosing a variety, the first thing to decide is whether you want to grow summer or fall raspberries. With summer raspberries, it’s possible to harvest the first berries in the same year you plant them. With fall raspberries, on the other hand, you can pick the first berries the following year.

Standard Summer Raspberry Varieties

Glen Ample Raspberry Variety

Glen Ample is an excellent standard variety among summer raspberries and is classified as a mid-early variety. It has a good flavor, with a pleasant sweetness and a slight hint of tartness. The fruits are large and round in shape. They stand out with an attractive medium-red color. Glen Ample produces high yields and has good harvest potential. The thornless, winter-hardy plant features medium-green foliage and can be easily cultivated as a long-cane variety. The individual canes grow upright and branch sparingly. It can reach a height of up to 200 cm, with a spread of up to 150 cm. Glen Ample is susceptible to cane diseases. This variety is ideal for direct marketing, retail, or processing.

Tulameen Raspberry Variety

The slightly later-season summer variety Tulameen is a popular standard variety that stands out for its excellent fruit qualities. Its berries are large, conical in shape, and firm. They feature an attractive, bright medium-red color. Tulameen delights with its sweet fruit aroma and consistently high yields, including good harvest performance. This variety is well-suited for cultivation as a long-cane plant. The shrub-like plant can reach a height of 180 cm and a spread of up to 150 cm. It is vigorous, with medium-green foliage. Thanks to its robust growth characteristics, Tulameen can be grown in almost any soil. The plant is vigorous but shows a slight susceptibility to leaf and root diseases, which should be taken into account. It is best suited for direct marketing and retail sales.

Standard Varieties of Fall Raspberries

Autumn Bliss Raspberry Variety

Autumn Bliss is one of the most reliable and earliest fall varieties, bearing fruit on the current year’s canes. Its fruits are very large, firm, and medium to dark red in color. It impresses with a delicious sweet flavor. Autumn Bliss stands out for its high yields, excellent shelf life, and good harvestability. This fall raspberry ripens from around early August through October. The hardy plant is resistant to common diseases.

Polka Raspberry Variety

The winter-hardy autumn raspberry Polka is a robust plant that is easy to care for. Polka produces a high yield. The fruits are medium to dark red in color and delight with a very good aroma. The fruit is very large, cone-shaped, and has a firm texture. The ripening period for this autumn variety is roughly from early September through October. The fruits have a long shelf life and yield well when picked. The shrub-like plant is winter-hardy, very robust, and, due to its late flowering, shows only low susceptibility to disease. The late-ripening Polka bears fruit on one-year-old wood and can therefore be pruned back completely in the fall without any problems.

The best time to plant raspberry plants depends on the type of plant. It’s also important to consider whether you want to harvest a crop this year or are planning to harvest for the first time next year.

Before planting, care should be taken to prepare the soil properly, depending on whether you plan to grow the raspberry plants in potting mix or in native soil. When planting the canes, dig a planting hole twice as large as the root ball. To promote better root establishment, loosen the plant’s root ball well before placing it in the hole.

To simplify pruning and maintenance, summer and fall raspberries should not be planted directly next to each other.

Planting Requirements for Plugplants

To ensure adequate growth, a planting density of six plants per meter is recommended for plugplants. Row spacing may vary depending on the machinery used.

• Row spacing of approx. 2.5 m = 24,000 plants/ha
• Row spacing of approx. 3.0 m = 20,000 plants/ha
• Row spacing of approx. 3.5 m = 17,200 plants/ha
• Row spacing of approx. 4.0 m = 15,000 plants/ha

Planting Requirements for Long Canes

For long-cane plants, six canes per meter are recommended. This corresponds to three pots, each containing two canes per meter.

Raspberry plants should be planted as soon as possible.

If it is not possible to plant them immediately upon receipt, it is important to store the plants in their boxes. A shady spot is best for this. The plants should be checked regularly and watered sufficiently until they are planted.

An essential part of raspberry cultivation is cane management and pruning. When determining the timing and method of pruning, it is important to consider whether the raspberries are summer or fall varieties. In general, diseased canes should be cut off immediately to prevent the disease from spreading to the entire plant.

Summer Raspebeeries

The first pruning takes place after the summer harvest. The brownish canes that were harvested this year are cut back to ground level. This is important so that the new green young canes that have already formed can grow vigorously.

The second pruning of summer raspberries is done after the last frost, around March. This pruning is essential for achieving the highest possible yield and good fruit size. The young canes are reduced to the desired number and cut back to ground level. It is recommended to leave 10–12 canes per plant. This ensures that the healthiest and strongest shoots are retained.

Fall Raspberries

Fall raspberries are pruned after the harvest season in the fall. At this time, all canes on the raspberry plant can be cut back to ground level. If desired, you can also leave a few healthy canes standing over the winter. In the spring, the plant will produce new canes again, bearing fruit for the next fall harvest.

Proper water and nutrient supply can be essential for fruit quality, fruit size, and plant health. If possible, the soil used for growing raspberries should have a loose structure to ensure good regulation of water, nutrients, and air. For your information, a soil test or analysis of previous crops and irrigation water can be very informative. This analysis will give you insight into the nutrient levels in the water, allowing you to take appropriate action.

Please note:

• A steady supply of water and nutrients is very important for successful cultivation
• Loose soil structure, if possible
• Initial watering without fertilizer—this stimulates root growth
• Water and nutrients are supplied primarily through drip irrigation

Special considerations for substrate culture:

To monitor water and nutrient supply, some drip water must be collected from the drip irrigation system. This is determined based on the EC value. Regular monitoring via EC measurements is essential. It is also important to ensure that the amounts of water and nutrients applied are adjusted to the plants’ growth. Initially, the focus should be on providing a predominantly nitrogen-rich supply, whereas in the fall, you should switch to a potassium-rich fertilization regimen. This helps the shoots harden off and reduces frost damage.

With 1-year-old or, at most, 2-year-old plants, there are fewer problems with canker diseases. Common problems in protected raspberry cultivation include spider mites, aphids, and powdery mildew. Beneficial insects have proven particularly effective in protected cultivation. Depending on the region and variety, problems with Phytophthora/root rot or overwatering have also been reported. It is especially important to be vigilant during a rainy spring.

Starting in July/August, daily harvesting and covering the crop with netting are very important to prevent cherry fruit flies as much as possible.

In protected cultivation, the use of pesticides is not urgently necessary, as susceptibility to pests is very low.

Generally speaking, raspberries do not need winter protection, as the plant is hardy.

However, for newly planted raspberries or those grown in pots, it is recommended to cover them over the winter with, for example, mulch, straw, or garden fabric.

Raspberries should be harvested every one to two days.

Care should be taken to pick the berries thoroughly and carefully. This helps improve the fruit’s shelf life and reduces the risk of botrytis infection.

It is recommended to place the berries directly into the display tray immediately after picking to preserve their quality as much as possible. Rapid cooling afterward is very important for the fruit’s shelf life.

Freshly picked raspberries should definitely be stored in the refrigerator. It’s best to use a shallow dish so that the berries aren’t piled too high on top of each other.