Nematodes

I believe I have mentioned our struggles with flea beetles before.

And I know that our customers have seen the damage they can do to our crops and understand our need to fight them.

This is what flea beetles do.

Unfortunately, it seems that everything we try is only partially effective. But today, we tried something new.

Nematodes. Specifically, 50 million Steinernema feltiae, soil dwelling parasitic nematodes that attack only insects. Mostly, they only go after the pests - like flea beetles, thrips, and fungus gnats - and leave the beneficial insects alone.

Click here if you want to see where we bought them.

This is what 50 million nematodes look like.

When you get them in the mail, you can't actually see them. All you see is a small package of "inert powder".

So, of course, we had to check and make sure they were really there.

They were.

Then we mixed some of them with water, did a test squirt through our sprayer, and checked under the microscope again to make sure they were still there.

They certainly were.

Finally, I went to the greenhouse and sprayed all the starts that flea beetles find especially tasty, such as cabbage, broccoli, and cauliflower. Tomorrow I plan to spread some in the field on the flea beetle hosts that we have already planted.

You can't see them, but I assure you they're now here too.

Hopefully, they will keep our flea beetle population under control this year. Cross your fingers with us!

Week 9: Nights in the 40's

It is lettuce weather again.

Pablo lettuce, one of this week's lettuces. In my imagination it's
named after Picasso because it is a work of art. But I suppose
several people are named Pablo.

This has been my year for experimenting with lettuce, I ordered something like 18 different varieties of head lettuce this year, so we have had it in the shares in some form or another nearly every week. But lettuce that grows through days that hit 90 degrees will never be quite as delicious as lettuce that has matured during a cool stretch (even if that lettuce is a carefully selected heat tolerant variety).

So, while a few cool nights will somewhat slow the harvest on the summer squash, cucumbers, and field tomatoes (and may halt the field peppers altogether), they will bring us some delectable lettuce this week as well. They will also help the late season cole crops along. I know I'm not the only one looking forward to Brussels sprouts.

Pirat, this week's other lovely lettuce. I've no theories as to the meaning
of its name.

The rest of the share is bulging with standard mid-season garden goodness. In addition to the head lettuce members can expect: Beets, Carrots, Summer Squash, Cucumbers, Tomatoes plus Eggplant/Peppers/Tomatillos OR Ground Cherries, Thai Basil, Scallions, and Kohlrabi or Broccoli.

We are continuing our quest to make sure that everyone gets to try the Thai basil, this week is the group one half share members' turn. I'm curious to know what everyone that takes tomatillos is doing with them. A few years back we had a glut of them in the fall and I came up with this recipe for tomatillo chili. It calls for two pounds, which is much more than is going in the shares right now, but it could be adjusted to make a smaller recipe or used as a springboard for a different chili recipe.

There is a break on Kale and Chard this week thanks to the flea beetles and aphids respectively. 

Impressive, no? Flea beetles like cool nights too.

We will wage what non-toxic battles we can and hopefully see them again in the not too distant future. In the meantime, if you are jonesing for some cooking greens keep in mind that kohlrabi leaves can be used just like kale.

Kohlrabi also makes wonderful coleslaw. As in the following recipe.

Kohlrabi Slaw

This is a pretty standard coleslaw recipe made, I think, exceptional through the use of kohlrabi rather than cabbage. I included a little celery seed, because I don't believe that coleslaw can exist without it, but it is entirely optional. It can also be doubled if you love celery seed as much as I do. The Thai basil is also optional, but adds a subtle twist to the flavor. Another fresh herb such as parsley or cilantro would work well in its place.

• One large kohlrabi, peeled and grated (it helps to quarter the kohlrabi before attempting this), plus four or five kohlrabi leaves, chopped into ribbons.
• Four carrots, sliced thinly
• 1/2 bunch of scallions, green and white portions, thinly sliced
• A small hand full of Thai basil leaves (about 12), finely chopped
• 1/2 cup mayonnaise
• 1/4 cup plain yogurt
• 2 Tablespoons vinegar (white wine or apple cider both work well)
• 1 Tablespoon sugar or honey
• 1/4 teaspoon celery seed
• Salt and freshly ground pepper to taste. I used about a 1/4 teaspoon of each as the mayonnaise was already pretty salty.

Toss together the grated kohlrabi, chopped kohlrabi leaves, sliced carrots, sliced scallions, and chopped Thai basil in a large bowl.

In a separate small bowl stir together the mayonnaise, yogurt, vinegar, sugar or honey, celery seed, salt, and pepper. If you are using sugar, be sure to stir until the granules have dissolved into the dressing.

Pour the dressing over the vegetables and toss until they are evenly combined. Let it sit for at least 20 minutes before serving. This holds well in the refrigerator for at least 24 hours (which was as long as our leftovers lasted before we ate them all up!)

Attack of the Flea Beetles

Flea Beetle on Rainbow Kale

Tiny hopping beetles in shades of metallic green or decorated with orange flame stripes, they would be cute. Would be, were it not for their evil streak.

I know that they are just doing what comes naturally to them (See the holes in that kale leaf. That is the nature of the flea beetle.) but I still choose to think ill of them.

As pesticide free farmers we are faced with an annual dilemma when it comes to the flea beetles. Flea beetles eat small holes in brassica plants, also known as crucifers or members of the cabbage family.

Because brassicas tend to do well in cool, short season climates like the Upper Peninsula, we grow about 15 different crops that flea beetles like to dine on.  As long as the plant being fed on is established the flea beetles don't really hurt it, they just cause cosmetic damage.

Like this:

Or this:

Seedlings are a different story. Hungry flea beetles can munch a radish seedling into oblivion if given the opportunity. 

So here is our dilemma. What do we do about this insatiable insect? 

We have a few tricks up our sleeves. Garlic oil sort of kind of helps a little. Row cover (see the photo below) helps even more by literally hiding the tasty brassicas from the beetles.  

Kale, Broccoli, Brussels Sprouts and Cauliflower in the foreground.
Two rows of mustard and radish seedlings hiding under row cover in the center.
Peas and Favas in the back.

So, we use row covers when we direct seed brassicas, to protect the seedlings. Sometimes we apply garlic oil to the row covers if the beetles find their way under. I'm not convinced that the garlic oil does anything but make us feel better though.

Our seedlings almost always survive with this treatment, but not unscathed. Our mustard and radish greens are always a bit holey.

And what about the kale, cauliflower, broccoli, and brussels? They are just left in the open to fend for themselves against the flea beetles.

We start those crops in the greenhouse, then transplant them into the field. By the time we plant them they are too big to hide under row cover, and they would have to come out sooner or later even if we could cover them at first.

There is a chemical option for treating the flea beetles. It's even allowed under many organic certification programs. Pyrethrin. It comes from flowers (Chrysanthemum cinerariaefolium) that look like oxeye daisies. It has been used for 100 years and is generally considered the safest insecticide to use on vegetables. Organic growers use it. It's probably okay, right?


Well...it is a neurotoxin to all insects, not just flea beetles. It is also toxic to fish. It can cause symptoms such as drooling, seizures, and death in humans (granted, only if consumed in large quantities - in small quantities it is completely non-toxic to mammals). 


Every year when the flea beetles attack we say to ourselves "We could use pyrethrin. It would work." And we decide not to.


We don't want to spray poisons on our food. We just don't. So the co-ops don't pay us as much for our arugula, our farmers market customers baulk at the holes in our kale, and we worry that the CSA members won't understand. That's the price we pay for our decision. We think it is the right one.