Vertical farms are more commonly associated with growing herbs, leafy greens and vegetables but these trials have proved that there is no barrier to successfully growing tree seedlings. The trials are being run by Forestry & Land Scotland (FLS) in partnership with precision indoor growing technology specialist, Intelligent Growth Solutions (IGS).
FLS has already completed five growing trials at the IGS Crop Research Centre, based at the James Hutton Institute in Invergowrie, just outside Dundee. Species that have successfully been grown at the facility include both conifers, such as Norway and Sitka spruce, Douglas fir, lodge pole and Scots pine, and broadleaf varieties, including oak, alder, aspen, rowan, hazel and birch.
Each trial has yielded better results than the last, with tweaks being made each time to the environment including watering regimes, light settings and nutrition. Tree seed germination rates are significantly more efficient (around 95% with a 10-14-day germination period) compared to traditional outdoor broadcast sowing.
FLS estimates the process will use around half the number of seeds currently required, a particular success for species such as native Scots pine and aspen, which have seeds that are difficult to collect. The vertical farm grown seedlings have already been planted out into the ground at FLS’s Newton Nursery near Elgin and have hardened off successfully (acclimatised to the outdoors to ensure new growth is sturdy).
A sixth trial now under way and will aim to actually slow the growth rate down to get a thicker root-collars on the seedlings, making them more suitable for planting out in restock forest. The vertical farming system is also expected to produce a more consistent product, which will then grow on for one or two years outdoors in fields, before planting out into forests. This is because the vertical farm controls all the conditions that matter to a plant such as temperature, light, water, wind and humidity to produce the optimum conditions for growth.