Could be phosphorus deficiency, maybe? Cold weather inhibits phosphorus uptake, and will cause tomatoes and peppers to develop red veins and/or a red tinge on the leaves, so I'm thinking it might have a similar effect on cabbage family in some cases.
How big are your cabbage plants? I know a seedling's leaves will turn purple on the undersides if it is kept too damp and too cold (like from a draft). This is akin to a baby turning blue when it's too cold...
Also, what amendments did you put into your soil? Are you in-ground or in a container? Could you possibly post a picture of your ailing cabbages?
I'm going on my 4th season growing cabbages, and never have encountered this malady. Will try to help as I can, but need a wee bit more information...
When I put my cabbage seedlings out, it was very windy, and cold, a sure formula for distressed babies (more so the wind than the cold -- these are cold weather crops -- but, sometimes that wind can do more damage than the cold!)
So, I put my hoop up on the windy days, and left the ends open for ventilation, just until they were well established enough.
oops. Those are the transplanted cabbages and cauliflower seedlings I put out very, very late. The hoop is off because the picture shows them after they'd grown much bigger than when I planted them out.
Here's a picture with the plastic cover on. Those are Brussels Sprouts plants underneath. I had to shift them out, cause they grew so tall, and I needed to put the late transplants out and under!
I've only eaten one serving so far. I've given away at least 5 heads of cabbage. Which is part of my growing mission. I'll give it away before I let anything go to waste or go bad in my veggie garden.
I have a neighbor whose "sweeter than cuties" tangerine tree is hanging over another neighbor's fence. Permission was given for the neighbor to eat as many fruit as they wanted. The neighbor invited me over and I got a bag of fruit. But, I noticed there were SCORES of rotting fruit on the ground, because this neighbor wasn't harvesting them fast enough.
Well, a few days later, I brought yet another neighbor to see the tree, and to ask if we could share some with that neighbor. Do you know there was an attitude of "don't take too many, now"!! I could hardly believe it.
Hi Linda... Yea... I don't like to see food go to waste either... I feel so dang guilty if I have to throw stuff out.
We've adopted more of a Paleo lifestyle so we're eating lots more vege's... mostly because we don't eat 'grains' any more. We've always eaten vege's but I used to make my 'coconut rice' for just about every meal... don't do that anymore... so replacing that with EXTRA veges. Looking forward to getting my big garden in this year -- I didn't do one last year.
My veggies seem to grow very slowly. I had planted my cabbage plants in Oct. I think or when WalMart starts selling their fall plants. And they are all making heads now. But as far as my Kale, & Lettace, they seem to grow so slowly. They are nice & green, but they stay one size. I fertilize some, with l0-l0-l0. Maybe I need to fertilize more.
If you do fertilize try more Nitrogen. It's great for foliage. I planted lettuce seeds in straight composted horse manure and they grew really fast. Just make sure you wash the leaves off really well before you eat them.