Containers Used For Hydroponic Berry Production
According to the substrate company Fafard container production of berries is widely used in Europe for example in Switzerland container production of strawberries quadrupled between 2002 and 2009 from 10 to 40 hectares. Soilless culture is being swiftly adopted due to its high yields but what containers are recommended for intensive protective cropping of berries? The following were looked at:-
Plastic grow bags
Figure 22 Galuku Coir 20l Grow Bag with black inside and white on outside. Yarra Valley, Victoria – October 2013. (Soure: N Mann)
Plastic grow bags come in different sizes and are the cheapest and not surprisingly the most common container used for raspberry and blueberry production in Australia and New Zealand and usually supplied by Galuku with dry coir already inside the bag. The grower just needs to wet the substrate which expands and fills the bag ready for the berry to be planted. The white on the outside is beneficial in a hot climate like Australia as it reflects the light and reduces the heat on the roots.
Figure 23 Black Plastic Grow Bag (Black inside and out). Haygrove, Ledbury, UK – April 2015. (Source: N. Mann)
Black plastic grow bags are commonly utilized in colder climates – these bags are robust and cheap. The dark colour absorbs heats and keeps the rootzone warmer which is an advantage in the cooler climates. It is imperative to have plastic bags slightly elevated to ensure appropriate drainage for the berry crops so diseases likes phytophthora, pithium and fusarium do not develop at the bottom of the bags where moisture can accumulate.
Weaved grow bags and different sizes
Figure 24 25l Polyweave Bags filled with Coir Blend. (Source: N Mann – NSW January 2014)
Figure 25 Polyweave growbags for hydroponic blueberry production. (Source: N. Mann NSW March 2014)
Figure 26 45litre polyweave bag from Garden City Plastics ( Source: N. Mann – Perth, WA 2013
Polyweave bags are common in Australia and these bags photographed above have robust handles to easily move the plants about. There are 2 common sizes used for blueberry production 25l bags and 45l bags. The later gives a larger rootzone and buffered area and maybe advantageous in year 7 and above if the roots become too dense and matted – however, it must be noted that most blueberries have roots that are only 50cm deep and usually only shallow and with regular and precise hydroponic feeding the roots do not have to over develop to source nutrients.
Figure 27 Square and Round Black Plastic Pots. (Source: N. Mann Portugal March 2015)
Figure 28 Plastic raspberry pots. (Source: N. Mann Sunshine Fruit Portugal March 2015)
The square 7.5 litre pots on the left were shown to encourage and maintain white healthy roots in raspberries (Hugo, 2015) compared to the same size pot on the right which was round. Both these containers were fitted with legs meaning they were held off the ground which is imperative for adequate drainage and to air prune any rogue roots.
Figure 29 Comparing raspberry roots from the square pot with the round pot. (Source: N. Mann – Portugal March 2015)
There is a new range of pots on the market from PlantLogic® with excellent drainage properties especially for the hydroponic berry industry – these are just beginning to be used and the results are still being established but they look like they have potential to add benefit to growers.
Coir grow bags
Figure 29 Coco-Peat Grow Bags with Strawberries. (Source: N. Mann Tasmania September 2014)
Coir grow bags are the mostly commonly used container for table-top production of strawberries. They are robust, relatively cheap and very convenient to use. Plant spacing, dripper spacing and drainage holes can be pre-determined and selected on ordering from the coir grow bag provider. The major disadvantage of the grow bags is disposal of the plastic sleeves once the media has been exhausted. Some growers are re-using the coir for year 2 of strawberry production but the heightened risk of root borne pathogens increases profoundly – however, it is a risk some growers are prepared to take for the cost savings achieved by doing so.
Figure 30 Recycled Polystyrene Broccoli boxes growing raspberries in coir. (Source: N.Mann NSW November 2013)
Re-cycled broccoli boxes made out of polystyrene can be used for raspberry production – they are relatively cheap and provide the added advantage of insulation against cold or hot temperatures. These particular boxes are filled with 2” of burnt ash beneath the coco-peat. This provides extra drainage ensuring the raspberry roots do not sit in wet, moist conditions which leads to ideal conditions for root pathogens. These robust boxes make use of a waste product which is looked upon favourably by consumers concerned with up-cycling & recycling – however, disposal of these containers does also provide a problem at the end of their life-span.
Figure 31 Low white tubs growing raspberries in coir. (Source. N. Mann Spain March 2015)
These custom-styled white growing tubs seen in Spain provide another option for growing raspberries – the side drainage slits are a concern if there are no other drainage outlets underneath these tubs, as moisture and water can pool in the base of the tubs increasing the conditions for root infections. These containers are good examples of what little substrate is required to grow hydroponic raspberries especially if the grower is skilled and in-tuned with the crop. The white colour also deflects the heat and protects the roots from over-heating in warm climates.
Figure 32 Shallow black tubs growing raspberries in coir. (Source: N. Mann Ireland March 2015)
These tubs are similar to shallow tubs seen in Spain – both used for raspberry production however these tubs are black and used in Ireland to absorb the heat to keep the raspberry roots as warm and active as possible. The white weed matting is also utilized to reflect as much light as possible back up to the plants above.