Flea beetles
All of the brassicas, except for radishes, start out under floating row cover. It’s the only way they’ll survive the flea beetles. Around here, the FBs are a clear and present menace to the cabbage family. They chew little holes in tender baby leaves until nothing but stems and dried out leaf skeletons remain. It’s awful. I could use organic sprays, like rotenone or pyrethrin, but although they’re “approved” and from natural sources (other plants), it seems to me a slippery slope, or at least habit-forming. I haven’t sprayed so far. I did try a garlic blender concoction as a repellent once, but it was like cooking for the FBs, they hopped off and hopped back on once the spraying stopped: salad dressing! Anyhow, this is bok choi (pak choi). FBs eventually managed to get under the edges and do a bit of damage, but that’ll be outgrown, bok choi grows fast (as do radishes). Once the leaves get a bit more substantial, the FBs can’t as easily chomp on ‘em. Cauliflower and broccoli, under this same 14′ wide sheet of row cover, are untouched. FBs REALLY like bok choi!
Somewhat related posts: • Radish without holes • Latest brassicas released • More hands on deck • Last big harvest of the year! • Crops for Fall
Jenny said,
May 11, 2007 @ 4:18 pm
Funny, I walked into my garden just today to find this same kind of damage on my eggplants and tomatoes. Since I read your post earlier today I was able to look up FBs and confirm that that’s what I’ve got. Thanks for identifying them for me, at least!
Mike said,
May 13, 2007 @ 8:51 am
Jenny: Yikes. When you look up these pests, besides their main interests, there’s usually quite a list of other crops they’ve been known to devour. Luckily, my regulars are conservative: the FBs stick to the brassicas and don’t include tomatoes, spinach or whatnot, the Colorado potato beetles stick to potatoes (and don’t hop over to eggplant or tomatoes), the cucumber beetles stick to the cucurbits (and ignore the peas, beans, etc). Yours seem to be more adventurous… Oooh. Doesn’t bear thinking about too much! :)
Wilbur said,
April 27, 2008 @ 2:34 pm
Anyone know what companion plants would keep the flea beetle off arugula? Nothing mentioned in Carrots Love Tomatoes.
Mike (tfb) said,
April 27, 2008 @ 4:55 pm
Wilbur: At least around here, flea beetles LOVE arugula, so if you have FBs and you grow organically, with no spraying, you’ll probably need floating row cover. If you take care to keep the edges of the cover pretty well pinned down, it does the trick with all brassicas. As far as a trap crop, mustard is an inexpensive brassica that FBs really like. They also seem to particularly favor bok choi. I haven’t experimented much with FB trap crops, but I imagine in smaller gardens, they won’t entirely distract FBs away from the crop you’re trying to protect, just lessen the attack.