• Improved nutrient uptake
• Promotes root growth
• Activates plant metabolism
• Promotes more even growth

Nov@ is rich in plant saponins and glycine betaine. It contains chelated trace elements, polysaccharides, amino acids, and vitamins that stimulate plant metabolism. Suitable for summer planting.

Suitable for organic farming.

→ Further information can be found on the manufacturer’s website:
Nov@ – Biolchim Deutschland GmbH – Special fertilizers, biostimulants

• Activates the plant’s own immune system
• Promotes vitality and growth
• Strong and resilient crops

LOKER AID is rich in polyphenols, polysaccharides, and vitamins. It promotes metabolism and restores balance after periods of stress. Polyphenols induce the strengthening of plant tissue and complement the effects of fungicides.

→ You can find more information on the manufacturer’s website:
Biolchim Deutschland GmbH – Special fertilizers, biostimulants

• activates the plant’s own defenses
• increased resistance
• strong and vital crop

Loker SA has a plant-strengthening effect, beneficial for resistant crops. It activates metabolism and supports vitality. Tolerance to powdery mildew is drastically improved. It contains no phosphoric acid, but does contain salicylic acid.

→ Further information can be found on the manufacturer’s website:
Biolchim Deutschland GmbH – Special fertilizers, biostimulants

• Strengthens plants, reduces stress symptoms
• induces the formation of phytoalexins
• stabilizes chlorophyll production and photosynthetic performance

Protamin Cu is a foliar fertilizer that works from the inside out, in combination with copper and amino acids. It helps prevent bacterial infections and keep the roots healthy.

→ Further information can be found on the manufacturer’s website:
Biolchim Deutschland GmbH – Special fertilizers, biostimulants

• For vegetation start and root development
• stimulates root growth
  (especially to support early emergence)
• promotes crop vitality

Sprint Alga stimulates primary metabolism, thus optimizing the hormone balance in young roots. As a result, rapid root development is stimulated. Apply after planting frigoplants (in spring).

→ Further information can be found on the manufacturer’s website:
Biolchim Deutschland GmbH – Special fertilizers, biostimulants

• Cold stress/heat stress/sunburn prevention
• optimizes plant vitality

BetaB consists of extracts of brown algae and alfalfa, as well as glycine, betaine, and folic acid.It supports the plant in stressful situations and optimizes its metabolism.

Suitable for organic farming.

→ Further information can be found on the manufacturer’s website:
Biolchim Deutschland GmbH – Special fertilizers, biostimulants

• For stabilizing plant tissue
• higher frost and heat tolerance
• resistant crops
• promotes high fruit quality and stable yields

BetaSil is a biostimulant that sustainably supports the plant through glycine-betaine and silicon. Glycine increases frost and heat tolerance. Silicon triggers genetic and physiological reactions in the plant by promoting betaine production, resulting in a thicker cuticle and the production of phenols and phytoalexins.

→ Further information can be found on the manufacturer’s website:
Biolchim Deutschland GmbH – Special fertilizers, biostimulants

• Easy to use
• Very high solubility
• Very good nutrient uptake
• No residue in the irrigation system

Green-Go nutrient salts are formulations acidified with citric acid which are fully water-soluble.

– Green Go 8-24-16 +10Ca
– Green Go 6-48-18
– Green Go 19-19-19
– Green Go 21-7-21
– Green Go 6-12-36
– Green Go 12-12-36

→ Further information can be found on the manufacturer’s website:
Biolchim Deutschland GmbH – Special fertilizers, biostimulants

Planning – Plot Requirements

At the beginning of the planning phase, it is important to decide on the location and cultivation method. Do you want to cultivate the plants directly in the ground or in a substrate?

Other important factors to consider are primarily the requirements of the plot. The most important aspects when choosing a location are irrigation options, soil conditions, and the site’s orientation. If possible, the selected plot should be sheltered from the wind.

Recommended tunnel layout

What´s needed?

1. Various specialized machines (dam forming, laying foil, screwing in ground anchors, etc.)
2. Mulch film
3. Drip irrigation
4. Fertilizer injection
5. Fertilizer Green or plugplants
6. Plant protection
7. Tunnel system
8. Fleece
9. Bumblebees
10. Straw

Roman Tunnel

The Roman Tunnel is a highly flexible system for the professional cultivation of strawberries, raspberries, asparagus, and other specialty crops. It is the ideal system for forcing strawberries or asparagus into the ground. Its size makes it well-suited as a walk-through tunnel.

• Standard width: 5.50 m – Available widths: 3.50 m – 6.50 m
• Length in 2 m increments, typically 50–120 m
• Primarily constructed with 32 mm steel tubing
• Various configurations and reinforcements available

Richel Tunnel

Richel offers a wide range of products, from the smallest polytunnel with a width of 6.20m to a fully equipped greenhouse. These are high-performance systems for the professional cultivation of strawberries, raspberries, asparagus, and other specialty crops.

OV90

• Models
Width: 8m – Sidewall height 1.96m
Width: 9.3m – Sidewall height 1.90m

• Robustness
  OV90 steel tubing with high elastic limit Arches that can be spaced up
  to 3m apart depending on the installation location
  Reinforced ends with additional supports and diagonal braces

• Load capacity
  Load capacity up to 40 kg/ml possible
Cultivation carriers also serve to reinforce against wind and snow.

Multitunnel

• Models
  Width: 6.20 m – Oval tube 60, sidewall height 2.20 m
  Width: 8.50 m – Oval tube 60, sidewall height 2.20 m
  Width: 9.60 m – Oval tube 90, sidewall height 2.45 m

• Improved productivity
  Optimized growing area on the broad sides
  Gable height up to 4.65 m
  Multi-bay tunnel construction possible

• Robustness
  Resistance to snow and wind loads

• Manual or motorized side ventilation optionally available

Zubehör Folientunnel

Unsere Partner bieten ein umfangreiches Sortiment an Zubehör, Zusatzausstattung und Verstärkungen an. Diese richten sich nach individuellen Anbaubedürfnissen und Regionen.

Films:

Film thicknesses

• 180/200 µm in Central Europe (UV stable for up to 4/5 years)
• 140/150 µm in Spain or England (UV stable for only 2/3 years)

Film properties

• Diffuse
• UVB-open
• Super-clear
• Anti-condensation

Light loss in polytunnels

• Approximately 10% through the film + 7% for each additional year
• Approximately 5% for steel pipes/structure
• Generally, approximately 70–85% light transmission in polytunnels and greenhouses

Rule of thumb from horticulture: 1% more light = 1% more yield

Before beginning the frame construction of a polytunnel, it is important to check that all materials are present to ensure a smooth process.

• First, the ground anchors are positioned across the width of the tunnel. Additional anchors are then placed sequentially in the ground at 2-meter intervals.
• The arches can now be placed on the ground anchors and secured.
• Next, the bracing/struts are installed at the tunnel ends.
• After attaching the ridge tape or ridge poles to the gable ends of the arches and the remaining materials, the tunnel cover can be installed. The cover is best installed in calm, dry weather.
• A gate system (e.g., hinged gate, roller gate, or FVG gate) is installed at the entrances. To allow ventilation inside the tunnel, professional tunnel models allow the cover to be rolled up from the side using a crank.
• Please note that a professional consultation is essential for planning and purchasing the appropriate tunnel.

Tunnel film:

• Standard film / greenhouse film: 180 mm thick, 4-year UV guarantee
• Raspberries, scheduled crops, etc.: Use special films with more beneficial properties

The following varieties are well-suited for cultivation in tunnels. Choosing an early variety can also support a planned earlier harvest period.

Raised Bed Cultivation

Raised bed cultivation is a familiar method that can be implemented with a variety of row spacings and planting densities. While this method does involve additional costs compared to ground-level cultivation, the effort is worthwhile due to slightly earlier ripening, higher yields, better fruit quality, and fewer diseases.
Strawberry plants thrive best in well-loosened and consistently moist soil. The raised bed also protects the plants from waterlogging, as excess water drains easily. The raised bed is created in the field using a ridging machine and covered with black mulch film (white mulch film is used for time-sensitive crops or delayed plantings, as it does not heat up as much). Drip irrigation lines are then laid under the film to ensure a stable supply of water and nutrients.

When using raised bed cultivation, the beds can be planted in single or double rows. The planting distance should be approximately 25 cm, with 3-5 plants per linear meter recommended for single rows and 6-8 plants per linear meter for double rows.

In cooler temperatures, the plants in the tunnel can be protected with a fleece cover; sometimes a double cover, consisting of fleece and perforated foil, is used.

Substrate Cultivation

Substrate cultivation is a specialized form of growing in greenhouses or tunnels. One advantage of this method is the ability to choose the location as desired, thus reducing the risk of many leaf and root diseases. Planting in substrate allows for cultivation in the same location without causing soil depletion.
The seedlings are planted in substrate bags or pots within a growing system, or directly in substrate mounds. This method often utilizes very robust tray, waiting bed, or Frigo A+ plants, enabling maximum yields. All systems are irrigated and finished with drip irrigation.
Specialized advice on fertilization and cultivation practices is essential for successful substrate cultivation.

Scheduling

Scheduling is particularly attractive in strawberry cultivation when you want to harvest a consistent supply of high-quality strawberries of a single variety over an extended period.

This cultivation method uses robust strawberry plants grown in cold storage or waiting beds. Depending on the weather, it takes approximately 7-9 weeks from planting to harvest. Planting is done at intervals (e.g., every 14 days) to ensure a long harvest season. In Austria, this cultivation method is only recommended for protected growing conditions and ideally in combination with shading or cooling of the plants.

Forcing Strawberries in Tunnels

To force the strawberry harvest, green and plugplants are typically used in tunnels and placed on raised beds covered with black mulch film. Planting is possible from the end of July to the end of August.

To achieve the greatest possible forcing effect, the tunnel should be closed in mid-February. However, this increases the risk of late frosts. The first rays of sunshine will help the plants begin to grow. If the tunnel is closed earlier in autumn or winter, ensure adequate ventilation to provide the plants with the necessary cold stimulus.

Another way to aid forcing is to cover the plants with fleece from the moment the tunnels are closed. The fleece remains on the plants until they begin to flower and is then removed. Sometimes a double covering of fleece and film is used. The removed fleece is always kept in the tunnel so it is readily available in case of late frosts and can be used to protect the plants.

Delay in Tunnel Cultivation

When planting in tunnels, it’s possible to replant the field after an early harvest for a second, very late harvest. For this, A+ plants (strong plants) or plants from the waiting bed are typically used and planted on raised beds covered with black plastic sheeting. The first harvest period for these plants is in September/October, and the second follows in spring.

General Information on Plant Cultivation

Strawberries are primarily cultivated in tunnels using raised beds. The beds are covered with black plastic sheeting and result in slightly earlier ripening compared to direct ground cultivation. When using raised beds, the beds can be planted in single or double rows. The planting distance should be approximately 25 cm, with 3-5 plants per linear meter recommended for single rows and 6-8 plants per linear meter for double rows. The recommended planting density for green and plugplants is approximately 4-6 plants per square meter.
An irrigation system with drip hoses is required for optimal water and nutrient supply. Since the focus of measures in tunnel cultivation differs somewhat from that in open fields, individual fertilization plans and plant protection measures are necessary and should be developed in consultation with a professional.
In cooler temperatures, the plants in the tunnel can be protected with a fleece cover; sometimes a double fleece cover is used.

Strawberry plants absorb nutrients almost exclusively through their roots. The leaves, on the other hand, are responsible for gas exchange within the plant. Various nutrients are already present in the soil solution, such as those from mineral fertilizers, the mineralization of plant residues, irrigation/rainfall, or the decomposition of humus. It is important to note that the nutrient uptake of some plants is often linked to the plant’s transpiration (calcium).

• Essential Nutrients
  • Water, Carbon, Oxygen
• Major Nutrients
  • Nitrogen, Phosphorus, Potassium
  • Magnesium, Calcium, Sulfur
• Trace Nutrients
  • Iron, Manganese, Zinc, Copper, Boron, Molybdenum
• Other Nutrients
  • Sodium, Chlorine, Silicon, Aluminum, Fluorine, Cobalt

• EC (Electrical Conductivity) = Electrical resistance in the liquid
• More ions in the solution = Higher EC value
• Used to measure the salt/fertilizer content in the water/soil
• Measured in microsiemens = mS
• For berries, EC is in the range of 1.2 – 2.4 mS in the aqueous solution
• High EC value
  • Risk of root burn
  • Smaller fruit
  • Higher Brix content
  • Better fruit shelf life

• In Water
  • Good: up to 0.35
  • OK: 0.35 – 0.7
  • Difficult: 0.7 – 1.0
  • Not to be used: above 1.0
• Drip EC
  • Measurement with an EC meter to monitor the fertigation solution
• Drain EC
  • Measurement with an EC meter to determine how much fertilizer has not been absorbed
• Total of drip and drain EC
  • As a guideline for developmental stages
• Substrate EC
  • Monitored with special (expensive) measuring devices

Ventilation in the Tunnel

The optimal temperatures for strawberry plants in polytunnels are around 20-25°C during the day and around 10°C at night. For early strawberry cultivation, temperatures can be increased to around 28°C, up until the beginning of flowering. Depending on the region and weather, ventilation begins at the end of March. The doors at the entrance of the tunnel are opened, and the side panels are rolled up. Initially, ventilation takes place during the day, except in rainy weather, and the tunnel is closed again at night when temperatures are cooler. From the start of flowering, daily ventilation (day and night) is recommended to ensure the blossoms dry thoroughly and that pollination is successful. Continuous ventilation helps maintain the firmness of the strawberries.

Important:

• Ventilate when temperatures exceed 25°C (77°F)
• 28°C (82°F) is suitable for strawberries in the tunnel
• Ventilate continuously from flowering onwards
• From fruit development onwards, the tunnels must be fully ventilated day and night
• Fruit firmness
• Monitoring options:
• • Min/Max Thermometer
  • Weather station with SMS alerts

Fertilization and Irrigation

A soil analysis is recommended before planting, as it can provide valuable information about water and nutrient availability. The existing soil moisture should also be taken into account. Irrigation is generally carried out using a drip irrigation system. In spring, depending on the region and weather, watering once a week is usually sufficient. During the harvest season, when temperatures are warm, watering should be done once or twice a day.

To ensure the plants receive sufficient nutrients, it is important to create or have a professional fertilization plan created. Fertilizer is applied using a fertilizer tank or a professional irrigation system. It is important that each variety is irrigated and fertilized separately.

Facts:

• Soil analysis before planting
• Fertilization plan created
• Fertilizer application using a fertilizer tank or professional irrigation system
• Irrigate each variety separately

Irrigation

To ensure plants receive sufficient water, it’s important to water them frequently with small amounts. If watering every 30-90 minutes, the recommended duration is 3-5 minutes. However, this can vary depending on the weather, growth stage, and substrate type. The first watering should be done approximately 2 hours after sunrise, and the last approximately 1-3 hours before sunset.
Almost every watering should include a small amount of runoff water, except in the early morning hours. Note that the parameters need to be adjusted at higher temperatures. In this case, a higher runoff percentage and a lower EC value are required. A light-controlled irrigation system can also be helpful.

Important:

• Calculate the maximum water supply requirement.
• Acid enrichment is necessary.
  • Systems require at least 24 hours to ensure the pH value is within the correct range.
• Always oversize the water reservoir; it will usually end up being too small.
• A dripper every 20 cm is optimal for strawberries.
• The irrigation system must be able to water the plant every 30–40 minutes.
• The bicarbonate content in the water must not be too high for berry cultivation.
  • It can be reduced by acid enrichment.

Plant Protection

The pressure of diseases and pests in polytunnels differs from that in open fields. Diseases and pests appear earlier. Residue levels in protected cultivation should also be considered. It’s important to note that Botrytis pressure is lower, while powdery mildew pressure is higher. Spider mites and aphids can develop very quickly in the tunnel, so regular monitoring is essential.

• Special considerations for protected cultivation:
  • Observe the indications and waiting periods.
  • Products may behave differently through plastic or glass.
• Pests develop very quickly.
• Main problems in protected cultivation:
  • Aphids,
  • spider mites
  • thrips
  • powdery mildew
• Fewer fruit rots and soil diseases.
• Beneficial insects can be used and establish themselves well.

Frost protection

To protect strawberry plants from frost, the tunnel must be closed and the plants covered with fleece when frost is forecast.

Harvesting

Strawberries should be harvested every 2 to 3 days. The harvest yield depends on the growing method. It is recommended to place the harvested strawberries in the sales tray immediately after picking to preserve their quality as much as possible. Subsequent rapid cooling is very important for the fruit’s shelf life.