The long days of early summer carry much promise for gardeners. This is the period of peak production — for weeds and many insect pests, as well as for our crops! It’s also the time to start many fall crops, or at least prepare a space for them. But the summer garden’s sprawl (and the teeming array of interactions it represents) can easily distract us from the rapidly approaching fall planting deadlines.
In previous articles (still accessible online at www.mountainx.com), I’ve discussed strategies for weed management and whole-garden insect control. But even the successful implementation of everything I’ve suggested won’t ensure that your garden isn’t plagued by troublesome (and time-consuming) infestations of some of the tougher antagonists, such as Japanese beetles and Mexican bean beetles.
In the standard home organic garden, hand-picking is often the preferred solution for dealing with these pests. And if you choose to go this route, remember that it’s a whole lot easier in the cool of the morning, when these insects are slow to take flight. At that time of day, it’s possible to shake large numbers of Japanese beetles into a wide-mouth pail. Put a bit of soapy water at the bottom of the pail and they’re kaput! This process, however, is going to take time — and, perhaps more importantly — focus that could be used to establish a fall garden.
Fortunately, an expanding array of biological aids is now available to help us protect our summer gardens. For example, the larval stages of Japanese, flea and cucumber beetles all develop in the soil, and applying beneficial nematodes can reduce the adult populations. These microscopic, unsegmented worms enter the beetle larvae and multiply inside, eventually killing them. Because the adult beetles can migrate from adjacent areas, however, you’ll probably also need traps, hand-picking and insect-excluding, super-light row covers to control these pests. But nematodes can definitely help. They have very specific environmental/climatic requirements, however — so ask your supplier for advice on release conditions, timing and tactics. Suppliers of beneficial nematodes include The Beneficial Insect Company, Peaceful Valley Farm Supply and Gardens Alive! These firms are also good sources for traps and lightweight, insect-barrier-type row cover.
As far as I know, only The Beneficial Insect Company carries the next control agent: Pediobius foveolatus. These tiny (smaller than a fruit fly) wasps are originally from India. In Flat Rock, I used Pediobius to completely control bean beetles and their larger, look-alike relatives the squash beetles. Since moving back to Celo, however, I’ve found Pediobius less effective, never completely controlling those pests.
At first, I blamed my diminished success on insufficient vigilance in scouting the enemy. Pediobius must be released at the first appearance of bean- or squash-beetle larvae. And my first year back in Celo, I missed that deadline by at least a week. The next year, however, I made sure to catch the first hatching and released my troops right on time. The results were better but still didn’t approach the complete control I’d achieved in Flat Rock. So now I have a different theory.
When I was in Flat Rock, Pediobius wasn’t commercially available; instead, I relied on the New Jersey Department of Agriculture for my supply. They provided 1,000 wasps at the price I now pay for 120. Nonetheless, I’m planning to get 1,000 wasps again this year, still hoping to match the success of my Flat Rock experience. If that doesn’t happen, my suspicions will rest with the cooler temperatures here in Celo. The good news is that Pediobius is a lot easier to establish than beneficial nematodes. You need merely be sure that the host larval stage of the bean or squash beetle is present and that you release the nematodes in the cool of the evening.
Occasionally, I also buy ladybugs and lacewing larvae, both of which feed on a wide array of insect eggs and small, soft-bodied insects. Ladybugs are cheaper and can be stored in the fridge till needed. Release them in the cool of the evening. Moisten the area where you’re working, and release only a few predators per plant that you know is infested with ladybug food (such as aphids, caterpillar eggs or beetle larvae). I recommend buying pre-fed lacewing larvae to control pests that feed on plants like onions. In my experience, other predators don’t easily control such pests, which are readily consumed by the voracious lacewing larvae.
If flower or onion thrips are a problem, the minute pirate bug is an effective but pricey solution. Establishing the Minute Pirate Bug requires only prey (or nectar- and pollen-producing flowers, in the temporary absence of prey) — that and remembering, once again, to release in the cool of the evening. I don’t recommend releasing praying mantises: They will eat as many beneficials as pests. This is not to say that mantises are not a beneficial; it’s just that they naturally occur at the appropiate population density for our gardens.
Finally, if you raise animals or bring in lots of manure, flies may have an unfortunate or even demoralizing effect on your enthusiasm for outdoor activities. I’ve found fly parasites to be highly effective at slashing fly population levels around the farm. Keys to success include not spraying for flies where you’ve released parasites, and leaving the top few inches of animal bedding/manure when cleaning out barns, chicken houses, etc. The latter precaution is critical, because that top layer contains the fly pupae that are hosting the next generation of parasites.
Hopefully, these predators can help you free up some time to get that fall garden on track.
Many fall crops (such as carrots, leeks, beets, kale, collards, rutabagas, chard and peas) should do great if you seed them in the immediate future (i.e., before mid-July at the latest). Some — such as parsnips, brussels sprouts and the chicories — should already have been planted (theoretically). But if you can find brussels sprout starts and get them in the ground pronto, you can still have a great crop. Likewise, if you seed parsnips right away and cover your seedbed with a white fabric to get the soil temperatures cool enough to enable them to germinate quickly (within 10 days), you still have a chance. Your odds of actually harvesting parsnips will increase greatly if you cover them with row cover in late October and leave it on through the winter. You should be able to harvest some decent-sized parsnips this fall and many more next spring. I’d sow the chicories — raddichio, escarole and dandelions — right away; unless we have a harsh early fall, they should still make it.
Other crops — such as diakon, turnips, watermelon, radish, kohlrabi and the Chinese cabbages — will do best if seeded from late July through early August. Start at the end of the first week of August with succession seedings of spinach, fall lettuces, baby white turnips, salad radishes, broccoli rapinni and scallions.
The local garden centers tend to carry a decent selection of broccoli, cabbage and cauliflower. Shop early, and try to have them in the ground by early August. If want to grow your own transplants, start them immediately.
Remember, if you plant your fall crops in mid-to-late August/early September, many won’t have time to mature — and others will end up becoming your winter-garden crops! Sometimes we’re blessed with an incredibly mild fall in which late plantings thrive, but beware: Murphy’s Law definitely applies to gardeners, too.