This is by far one of my favorite summertime vegetables. I have a lot of memories of sitting around with my dad eating it raw, sliced with salt on it. (Just the thought of it is making me drool right now)
The year before last, they did really well and I had much snacking. Last year, I tried to do them in pots, however, and they really didn't like it. I think it once again has to do with the two weeks where it was ridiculously hot and I couldn't keep anything watered properly.
This year, I'm again growing Kohlrabi, and am planning on doing some in pots and some in the garden, with the hope that I'll get at least something from my garden to eat this year. This is a type of plant that you will want to grow in succession, so that you keep having harvests throughout the year. planting one mound every 2-3 weeks is ideal if you have the space.
I started these in eggshells on 3/4/12, and will start another set on 3/25/12, and then another sometime in April. After this time, I'll start the seeds in the ground directly as the weather should be consistently warm enough. Start them at a depth of 1/2" in a regular seed starting mix. They typically take between 10-14 days to sprout, but these little guys sprouted in less than a week!
They really need to have their own space, otherwise they will check they're own growth. If you plant these in containers, fertalize them moderately every 2-3 weeks and maintain a regular supply of water.
You'll harvest these in about 55 days, and try to pick them when they are between golf ball and tennis ball size, because when they get large, they tend to become woody. They can be stored for a little while, but tend to lose flavor the longer they are stored.
This year, I'm really hoping to get a good crop, as I found this recipe that looks like it would be great to try! I've never actually tried cooked kohlrabi, so I'm hoping this year's crop is a success.
Kohlrabi Sauteed in Butter
Peel any tough skin off kohlrabi, trim and scrub. Boil whole for 20-30 minutes, then drain, cut and saute in a pan for a couple of minutes with melted butter.
The leaves are also said to be good boiled.