Kohlrabi is a cool season brassica - it's less heat tolerant than broccoli but it can be grown in Kihei during our cooler months.
I planted kohlrabi seeds in mid-October when I started the other brassicas but that was a month too early. The seedlings were heat and sun sensitive and only one Purple Vienna survived a normal Kihei November. Next fall I'll wait until late November or December to plant seeds.
Purple Vienna Baby Greens
Kohlrabi is most tender when the bulb is around 2 inches wide. It grows faster than broccoli and can be harvested in about 60 days. Kohlrabi can also be sown densely and grown as a salad green.
The kohlrabi grew very well in a 5 gallon self-watering container filled with a natural and organic potting soil. I amended the soil with an organic all-purpose fertilizer and green sand and added the organic fertilizer again at 1 month intervals. The cabbageworms will attack the kohlrabi leaves - I recommend covering the plants with row covers or tulle tents.
Lots of info about growing Kohlrabi can be found here:
Kohlrabi makes great chips - raw, baked, roasted or fried in butter or olive oil.
Crisp Kohlrabi Chips
Baked Kohlrabi Chips
Roasted Kohlrabi Chips
Cultured Kohlrabi Sauerkraut