Kale has become a popular hydroponic crop due to its diver-
sity of types and growing interest as a healthy superfood.
Unlike cabbage, broccoli, and cauliflower, which form a head
at maturity, kale can be harvested at any stage and grown
as a short-term crop where required. Kale grown for baby
leaf production can be harvested within two to three weeks,
and a number of light and dark green and intensive red/
purple varieties are available. Some of the more unique kale
types include the blue/green Italian Lacinato, or “dinosaur
type” (Tascano) kale with elongated, heavily savoyed leaves.
These types are more tolerant of the warmer conditions that
may be run in mixed species indoor gardens.
NEW AND LESSER KNOWN BRASSICAS
A number of newer, specialty brassicas are an exciting poten-
tial for hydroponic growers. These include flower sprouts, which
are the result of breeding crosses between Brussels sprouts
and kale. These produce colorful rosettes of leaves in shades
of green, red, and bicolor that develop on the sides of stalks
of upright plants in a similar way to Brussels sprouts. Flower
Green cauliflower is one alternative to the traditional white curd.
sprouts have a unique, tender flavor (similar to kale) and have
developed a niche market as a gourmet veg.
Asian and mustard green brassicas include a range of Chinese
and Japanese species growing as specialty vegetables. Mizuna
and mibuna are common salad mix ingredients while others
such as misome and tatsoi produce compact, Asian greens more
commonly used in cooked dishes. Pac choi (bok choy) is one of
have considerable potential under
the most widely recognized Asian greens with a mild mustard
flavor and, for hydroponics, the mini versions — six inches at
hydroponic
maturity — perform particularly well. Asian mustard greens
consist of many different leaf types which are often savoyed,
may be light or dark green or intense purple with a hot, spicy flavor.
Mustard types are more commonly grown as baby leaf or microgreens in
hydroponic systems for both their attractive foliage and distinctive flavor.
Watercress is one of the oldest known leaf vegetables consumed by
humans and in more modern times, perhaps the most commonly grown
commercial hydroponic brassica crop. Watercress is well-suited to solu-
tion culture and grown for both baby leaf and full-sized production. With
its peppery, piquant flavor, exceptional nutritional value, and rapid
growth rate, watercress is one of the easiest hydroponic plants to
grow and takes up little space if kept well-trimmed. Watercress
plants can be started in hydroponics by simply buying a fresh
bunch and inserting the lower stem end into a container of
nutrient solution or straight into an NFT channel. Roots rapidly
develop from the stem nodes and new plants will be growing
fresh foliage within a week or two. Watercress can also
be started from seed, scattered onto the top of stonewool
cubes or damp growing substrate for later planting out.
While watercress prefers a flowing nutrient solution,
it can also be grown in static raft or float systems with
nutrient levels similar to those required by lettuce.
Radish, turnip, and kohlrabi are underutilized
crops that grow prolifically in shallow substrate-
based hydroponic systems. The common radish
now comes in a diverse range of shapes, sizes,
colors, and pungency with modern hybrids being
incredibly quick to grow (21 days to maturity)
for small salad types. The large, white daikon
radish, a staple of Japanese cuisine and
also grown for the production of kimchi,
produces spectacular-sized specimens under
hydroponic nutrition and makes a unique
addition for a mixed garden. Baby turnips and
the lesser known kohlrabi add diversity to a
mixed vegetable system and can all be grown
together on the same nutrient formulation.
“BRASSICA SPECIES
PRODUCTION.”
38
Maximum Yield