Cabbage family failure with leaf curl.

[Vanisle_BC]

I'm seeing a number of plants - all coles I think - becoming stunted, with tightly curled leaves. On opening the leaves I see no insects. Any opinions on what this is and how to deal with it?

[applestar]

I HATE to say it. I held off hoping for some other comment … but have you tried pulling up one or more plants and checking the roots for lumpy galling … which could indicate clubroot— a very serious soil borne disease. I had to stop growing cole crops for 3-5 years a while back.

[Vanisle_BC]

Apple, can you describe what clubroot would look like. I did pull up a couple but wasn't sure what to look for. Just assumed that the very tight leaf curl would indicate an above ground problem?

Bad enough that I lost most of my garlic to white rot and can't put alliums in that bed again.

[applestar]

Clubroot causes galls or lumps to form on the roots. At mildest it looks a bit like inoculated pea or bean roots, but as the condition worsens, root hairs and branching roots stop growing and there is nothing but stunted stubby taproot clustered with lumps.

[Vanisle_BC]

I think I found the culprits; see photo. They're tiny - smaller than aphids? They look grey to the naked eye but enlarged I see they are green. What would they be and how do I dispose of them? I'm spraying with Safer's soap for starters but it's hard to get down into the tightly curled baby leaves in the center.

[applestar]

Yep those are actually called CABBAGE Aphids. You want a sprayer with long nozzle. There are specialty sprayers like that — maybe for lubricating?

Sometimes skinny straws like coffee stirrers or box juice straws would fit tightly in front of regular hand held sprayers.

You probably know this, but the trick with dealing with aphids is to wet them down with the soapy solution, which makes them stretch up on their tippy-toes so as to lift their breathing orifices near their legs up high, thereby loosening their grip on the plants, then come back in about 5 minutes and blast them off with water.

[Vanisle_BC]

Thanks, Apple. Some good tips. I did know abut using soap and/or water blasting, but not all those intimate details about how the little critters behave.