Cover Crops Pest control

Oil Seed Radish – Brassicas — And a bug story.

I got so caught up with wintersown this year that I couldn’t stop planting.  I planted from Dec. 25th last year until June of this year.  In addition to succession planting of things I always plant, I added a lot of new things to the menu.

Most of what I added  were members of the brassica genus of plants — collectively known as cruciferous.  Included were cabbage, broccoli, Russian Kale, various chards, Hakurei turnips, and mazuni. (Radishes I always have.)

In retrospect an alarm should have gone off in my head signaling the possibilities of problems with Harlequin bugs and cabbage worms since these plants are their favorites. But that didn’t happen and I kept planting and couldn’t have been more delighted with the way things were growing.

And then what happened?

Everything was absolutely beautiful until June.  All of a sudden holes started appearing on my beautiful kale, chard and turnip leaves. The mizuna leaves, turnips leaves, kale, and chard had white blotches on them. They weren’t beautiful long.

Between those little green cabbage worms and the Harlequin bugs I had a battle on my hands.  I thought for a while I was winning but I lost battle and had to fall back and regroup.

Regrouping — Deciding what I want the Most

Of all the new things I grew, I absolutely loved Mizuna, Russian Kale, Chard and Hakurei turnips.  I have to find a way to have at least Mizuna and Russian Kale for fall planting and early spring. (And of course — as always – I have to have radishes.) The others I’ll worry about later.

The Origin of the Problem

A little slow on the uptake — I’m just figuring out tonight when it was the problem with the Harlequin bugs originated. Let me explain:

For years I’ve always had a few harlequin bugs in my garden, but not many.  I never really noticed any damage they were doing.  (Probably because except for radishes I didn’t grow Brassicas.)

I usually plant oil seed radishes as a cover crop after my potatoes because they pull up nutrients from the soil.  I let them grow until just before freezing and them turn them under.

Last year I planted more rows in oil seed radish than usual.  After they were up about 6 inches I noticed that many of the leaves had those white blotches on them.  Not having had to concern myself before with Harlequin bugs — I didn’t make the connection with the Harlequin bugs.  (The white blotches are where they suck the plant’s juice out.)

It had to be those extra rows of oil seed radish last fall that gave the bugs a foot hold.  It was June of this year before I realized I had a problem. They were multiplying.

Strategy to bring back the Balance

  • The closest I can come to turning lemons to lemonade is go out tomorrow with my shovel and turn under the oil seed radish.  They’ll still decay and add organic matter to the soil, but won’t play host for the Harlequin bugs. After a week or so, I’ll sow buckwheat or oats in those same beds as a cover crop that will winter kill and still protect the soil in the winter.
  • I’ll remove any brassicas that remain in the garden.
  • Will continue to kill any harlequin bugs I may find.
  • My fall planting of mizuna and Russian Kale will be where brassacias were not planted this year.  (They’ll go through the winter under protection of a makeshift coldframe.)
  • I’ll prepare a spot in the garden and one in the border.  (The spot in the border is backup — just in case the bugs attack in the garden.)
  • Next spring as soon as my Russian Kale seeds, I’ll save seed and remove it from the garden and wait until fall to plant again since I’ll have lettuce during the summer that will satisfy the graving for greens.
  • I’ll plant chard but much less of it and in a shady spot where they seem to do best. It gets huge and 6 plants should be more than enough. We usually have a meal of greens at least once a week.
  • I’ll limit Hakurei turnips to early spring. I think I can live without them in the summer since I have an abundance of other things.
  • Since I’m not planting cabbage or broccoli I may not have trouble with the cabbage worm, but I’ll be on the look out just in case.

Moral of the Story

If you plan to have numerous vegetables in the same family of vegetables that you’ve never planted before, do a little googling to find out what pests attack that family of vegetables.  If you’re prepared and address the problem up front — it won’t get out of hand.

Makes life much easier that way.  Ask me how I know.


Related Posts:

Evaluating ROI – Broccoli and Cabbage or Anything Else

Organic Pest Control – Two Stories

Cover Crops – Benefits – Some easy ones


Organic Gardening is easy, effective, efficient — and it’s a lot healthier.


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