Planting Kohlrabi

I think it’s safe to say we’re having an early spring here. The asparagus popped up a full three weeks ahead of when it did last year, and the raspberries and blackberries are leafing out as well. I also monitor soil temperatures, and this morning around 10am it was 52°F at a four inch depth. That tells me it’s time to start planting brassicas like broccoli, cabbage and kohlrabi. With rain forecast tonight and tomorrow, I decided to try and get a few things done today while the weather was dry.

I got one 4ft by 4ft cold frame bed planted with kohlrabi. Yes, that’s a lot of kohlrabi but my wife and I are both big fans. I prepped the bed first by adding compost and a complete organic fertilizer then working it with a fork. This year I’m growing Kolibri, Winner, Kossak and the 2016 AAS winner Konan. Kossak gets quite large and benefits from a wider planting, so I will save it for the main garden. I’m excited to be growing Konan for the first time. It was bred by Bejo Seeds, the same folks who gave us Kolibri and Kossak. I’ll plant some of it and Kolibri in the main garden along with the Kossak, in addition to what I planted in the cold frame bed.

I started all the brassicas this year in 72 cell plug flats. The plants are now four weeks old, and most have two or three true leaves showing. That’s about the stage I like to plant them in spring, though for fall I tend to let them get a bit bigger because birds seem to bother them more then. The larger plants usually aren’t as attractive to the birds as the smaller, more tender ones are. For whatever reason, the birds don’t usually bother them here in spring. Slugs and sowbugs do wreak havoc with them in all seasons, and I spread Sluggo Plus around the plants after planting. You can see in the below photo the roots are nicely formed, but the plants are not rootbound yet.

I’ll mulch around the plants later with some aged straw to keep down weeds and conserve moisture. I used about a 6 inch by 8 inch spacing this year in the bed, which let me get 35 plants in the 4ft by 4ft bed. I could squeeze them in a little closer, but I tend to let my kohlrabi size up a bit and this spacing seems to work well for me. I leave a little extra room around the outside so the leaves don’t get smashed by the coldframe lid. After planting I watered the plants in with a fish emulsion/seaweed mix to get them off to a good start.

I also worked up the spot in the main garden where I plan on planting brassicas, potatoes and onions. I sent off a soil sample to Logan Labs last week, and as soon as I get the results back I will come up with a plan for amending the soil in that area. Hopefully it will not involve any nutrients I don’t already have on hand, or can’t obtain locally. I need to go get my seed potatoes too and get them cut and ready to plant.

As long as we don’t get too much rain, with any luck I should be planting onions and the rest of the brassicas on Good Friday!