In response to recent questions, here are some suggestions from our friends at Grow Pittsburgh:
Flea beetles are a tough one. The best practice is to prevent them in the first place with barriers like row cover. Once the population is established, the only organic thing to do is control them so they are not eating so much of the crop that it is inedible (scarred and stiff kale) or left with too little foliage to survive. Some ways to do this are insecticidal soap and sticky traps. Trap crops are also something to consider – some gardeners will plant a patch of radishes to keep the flea beetles off a nearby crop of kale or collards.
The only other advice I would pass on is to be patient. Collards don’t do great in hot weather – they prefer the spring and fall temps. So, as you can imagine, the excessive heat this summer has been hard on them. As long as they survive (they can usually pull through, even with pretty severe flea beetle damage), they should do much better in the fall – and they will be one of the last crops you can harvest in the garden. They may even overwinter!
