BUILDING A SMALL FLOAT SYSTEM
Float systems are ideal for indoor gardens where space is
limited or where a crop needs a different EC than others in
the growroom. All that is required for the nutrient pool on
which the plants will float is a container (food safe, prefera-
bly) with a depth of at least four to six inches. The length and
width of the container depend on the number of plants to be
grown. Most medium-sized lettuce grows at a spacing of eight
to 10 inches square, but baby leaf greens and many herbs can
be planted at a higher density.
There are many material options to choose from when
making small-scale raft systems. Hydroponic pond systems
have been constructed from children’s paddling pools, fish
tanks, glass aquariums, food storage containers, buckets, and
plastic-lined timber frames—anything that creates a leak-
proof, lightproof, and level container works. The floats can
be constructed from closed-cell polystyrene, which is avail-
able from hardware stores. The polystyrene should ideally be
25-40 millimeters thick for maximum flotation, and the float
should be restricted to a size that can be easily handled and
lifted from the surface of the nutrient pool once plants are
mature. Holes in the dimensions of the tubes or pots used to
hold the plants are then cut or burnt into the float.
Top: A small-scale green onion float system. Bottom: Floats must be
sturdy enough to be handled when supporting mature plants.
72
Maximum Yield