“Food for thought” – 3 crops for commercial vertical farming

Pea shoots, watercress & cereal grasses (wheat/barley)

There is no shortage of options for fresh produce that can be grown hydroponically. Here, we highlight 3 possible crops that are relatively straight forward to cultivate and harvest, and can also be commercially viable in Wales with the right route to market in place.

The food market in the UK is largely influenced by three main trends.

  1. Demand for convenience.
  2. Concerns over health impact of diet.
  3. Desire for high quality at good value.

Following 2020 trials, here are three crops we would highlight as having good potential for generating a profit for a new entrant to vertical farming.

CROP 1: Pea Shoots
Pea shoots are pea plant harvested at a very young stage of growing, and typically includes 2- 4 leaf pairs and immature tendrils. They have a subtle pea flavour and a light, crunchy texture. They have grown in popularity especially in fine-dining circles, and are now entering more mainstream eating locations.

Growing: Pea shoots can be easily propagated from seed. Pea seeds will need soaking before being placed on a pre-moistened growing medium. It is important to double the volume of water to seed as they expend during soaking period. Sowing rate up to 2kg/m2.
Harvest: Most pea shoots will be ready to harvest within 2-3 weeks. Yields of up to 2kg/m2 can be expected. They need good airflow in order to avoid mould growth. Processing and getting to the market: Shoots could be cut with a sharp knife/scissors or be prepared in their growing medium. Shoots need to be dry when harvested for best shelf life to be achieved. Shelf-life potential can be up to 10 days chilled. Further value can be added through adding as a compliment to other products such as salad leaves or processed to make innovative products such as pea shoot pesto. In 2020, Tech Tyfu distributed samples of fresh pea shoots to a number of leading restaurants on Anglesey, and within less than a day, 3 out of the 5 were asking how to order more. Tech Tyfu has developed a logo that growers can use to brand their freshly grown pea shoots – contact for more details.

 

CROP 2: Watercress
Watercress is famous for its characteristic flavour, and as the name suggest, is a waterloving crop that can be grown very successfully in hydroponic systems.

Growing: Watercress can be easily propagated from seed. Seeds will need to be soaked before sowing on the surface of a pre-moistened growing medium in a “ebb and flow” system. As the seeds germinate freely, they should be sown thinly. An alternative approach to growing on matting is to sow 10-20 seeds per 2-inch net pot.  Harvest – Seed  sually germinate within 3-5 days. Watercress plants will continue to grow and can be repeatedly harvested over many months. After the flower buds appear, the leaves become flavourless and inedible. Good ventilation is essential with a fan system required to stop leaf burn during the summer and to stir young seedlings for at least 2 hours every day to stimulate shorter, sturdier, and more natural plant habit. Nutrient requirements is relatively low.
Processing and market – Watercress can be sold fresh for culinary uses or various salad leaves could be combined to create a healthy salad mix. Watercress does not have a long shelf-life. In a fridge, they can last for 2-3 days. Rockwool grown plants can be harvested and sold with roots still intact in growing medium. In 2020, local grower James Hooton from Hooton’s Homegrown, Brynsiencyn, successfully cultivated and harvested a crop of vertically farmed watercress. Branded as ‘Anglesey Watercress,’ each harvest was sold out at his popular farmshop. A 100g bag of freshly unwashed watercress retailed at the farmshop for £1.99. James is pictured below with Dr Luke Tyler of Tech Tyfu.

 

CROP 3: Cereal Grasses – Wheatgrass/Barley
Cereal grasses are considered to be very healthy and nutritious. They are a popular addition to many health juices as well as smoothies and other beverages. A wheatgrass ‘shot’ is made from juicing freshly cut wheat grass to produce a 40-50ml shot that can sold for £2.50- 3.50. A fresh shot is nutrient-dense and packed with vitamins and will contain various antioxidants and is one of the best sources of living chlorophyll.
Growing – wheatgrass/Barley can be easily propagated from seed. Seeds should be soaked before sowing on pre-moistened growing medium. Harvest – Cereal grasses will be ready to harvest within 7-10 days. Yields of up to 650g/m2 can be expected. Although the shoots will regrow, this is not recommended, as the nutrients in the second harvest won’t be as high as that of the first. Processing and market – Shoots could be cut with a sharp knife/scissors or be sold growing in their growing medium. Shelf-life potential is usually 7-8 days when kept refrigerated. Alternatively, freshly harvested cereal grasses could be juiced immediately and sold as ‘shots.’ Fresh juice can be kept in the fridge for up to a week.