Tuning the Dial: Planting Times Foil Insect Pests!
Take your time and read this post carefully. You may decide to change planting times for some of your plants.
One of the simplest ways to reduce pest problems is to stagger your plantings. Another is to adjust your planting times to avoid peak pest times, or just don’t plant that plant at all! Pests have life cycles per heat, water, light, humidity. They like only certain parts of your plants, maybe the leaves, or the flowers! If you have no crop for them at their time, no plant at the stage of the plant they prefer, you have a clean garden! Some insect pests carry diseases that infect the plants they prefer, and those diseases can spread to other plants as well. If you know your pest’s cycles and preferences, you can plant to avoid them completely! If you have a crop in, and know when the pest is likely to occur, you can keep a closer watch, and use your organic techniques to immediately repel or remove them.
Contrary to old-time thinking, as Cornell U says: ‘IPM (Integrated Pest Management) programs stress suppression of insect and disease populations to levels that do not cause economic damage, rather than total eradication of a pest. In the case of insect pests, it is important to have at least some pests present to ensure that natural enemies will remain in the crop to suppress subsequent infestations.’ Better to plant host plants for beneficials insect predators, and keep a healthy balance. You will have some loss, but a lot less.
Through Cornell U, a pest weather prediction service called NEWA, calculates factors daily and is available to the public! They call the Tomatoes diseases forecast the Tomcast! When you are looking online, be aware of what area the forecast or pest life cycle info is coming from, like Cornell is in New York. If it is much different from your area, you will need to adjust your timing. Keep a record of your local pests and diseases times. That can really help with your choice of planting times in the future.
Life Cycles and Planting Times to avoid common insect pests:
Flea Beetles About.com says: Adult flea beetles overwinter in leaf litter, garden debris, or other sheltered places. As temperatures begin rising in spring, the adults emerge and locate suitable host plants on which they feed. Some flea beetles will feed on weeds until garden crops are available. In late spring, female flea beetles lay eggs in the soil around the base of host plants. Tiny larvae feed on roots and root hairs for about a month, and then pupate in the soil. Multiple generations of flea beetles may occur in many areas.
UC IPM says: [Flea beetles] feeding on plants younger than the 4- to 5-leaf stage can result in stand loss, especially under hot, windy springtime conditions when the injured plants are desiccated. And, it turns out, the early flea beetles do the most damage, young and hungry, getting established in their best conditions. So be especially careful with your first plantings.
REMOVE DEBRIS, WEEDS at the end of each season, and before planting to be sure, break their cycle, lower populations. Betcha those little larvae are already munching. Ok, so disturb that soil around the base of your susceptible plants. The healthiest way to do that is to sidedress/fertilize them. That will turn those eggs and pupae under, or expose them to dry and die, plus your plants will be fed! Don’t dig so deeply as to injure your plants’ roots. ‘K?
We notice our flea beetles on short cycle plants, like arugula and radish. The simple thing to do is just not plant them May and June, especially after a mild winter. Or, grow them as trap plants to protect your eggplants! For example, plant the radishes first, letting them sprout, then put in your eggplant transplants. Keep planting the radishes until flea beetle season is over in your location. You will know when that is, it’s when your radishes no longer have those trillions of tiny holes in their leaves.
White Fly We have White flies and aphids right now Feb/Mar. Online it says to plant earlier in the spring and short-season varieties late in the fall to avoid high infestations. Clearly, we can’t plant summer crops earlier because the ground temps are too cold, and this is high planting time for the first summer crops, so best I can say is use row covers. If you don’t, keep a diligent watch and keep hosing them away! Delay the planting of fall vegetables until whitefly migration has diminished: use physical barriers, that’s row covers, during heavy migration; or, plant tolerant crops during these periods.
White flies are double bad. Whitefly infestations leave a parasitic fungus called black sooty mold, and that attracts aphids and aphids add to the black problem. Plus, whiteflies also spread viral diseases between plants. Plants infested with whiteflies will appear weak and stems and leaves that have the black sooty mold/fungus turn yellow and fall. It’s easy to know when you have them, because if you brush the plant, clouds of them fly about. Hose ‘em all, several days in a row to get rid of them, being sure to get under the leaves!
Aphids Aphids do it all year-long birthing as many as 12 a day! That’s long odds in their favor. If ever there were a reason to plant habitat for their predators…. Aphids form total colonies in leaves that have curled from having their juices sucked out, thus protecting the aphids. Once they are hidden, they are a nuisance to have to get to with the hose. Better to get to it at first sighting. They love the budding stalks of broccolis, the convoluted leaves of curly leaf kale. Syrphid flies larvae are their natural enemy; they can eat an aphid a minute! These flies are actually those little bees that hover, hover flies! You’ve seen ’em. Plant ample habitat for them. Aphids prefer 65° to 80°F, sigh. Some say marigolds, the scented kind, repel aphids, but IPM lists aphids as one of marigold’s pests.
Leaf miners are the larvae of many different insects. Somehow, that’s just not fair. Any temp over 50 degrees, and for the most part they are happy, but they love the 70s. There are 3 stages of growth while they burrow in the leaf, so better to remove the damaged part ASAP before it gets worse as they get bigger, and the pupae drop into your soil to start another 3 week cycle. They usually won’t kill a plant, but they can sure reduce its vigor, slow its production, make it susceptible to diseases, besides making your plant just plain ugly. The miners love chard, but aren’t picky. They also eat bean, beet, carrot, celery, cucumber, eggplant, lettuce, melon, onion, pea, pepper, potato, squash, and tomato. Equal opportunists. Damage is very noticeable on chards because of that ugly blotch on an otherwise great big beautiful expanse of dark green leaf. Unprotected chards do fine in our Mediterranean winters. If you do summer chard, use row covers. If your plant is struggling, and you just don’t have time to take care of it, especially if it is an old plant, just have mercy and do the one cut prune, do not compost or chop and drop. Wait until cooler weather and plant again, maybe some Bright Lights!
Cucumber Beetles are repelled by radishes! So if you plant your eggplant in front of your cucumber trellis, and radishes among them, you get double duty! The flea beetles munch the radish, and the radish repel the cucumber beetles! What a dance! Zucchini acts as a trap plant for muskmelons and cucumbers, and is less susceptible to beetle damage, a win win! Floating row covers are a much safer solution. Or if you use them, it takes foliar contact insecticides twice a week. Row covers must be removed when the plants start to bloom and need pollination, which, ironically, the beetles can help do. The beetles start to diminish at flowering time, and the plants can produce before they show symptoms from beetle damage. These cute yellow-green black striped little bad beetles carry bacterial wilt of cucurbits, that especially affect muskmelons and cucumbers. This is by far the worst thing they do. Sick cukes look wilted, like they need more water, then abruptly die. There is no cure. It’s the wilt. Saladin is a resistant variety of cucumber. Watermelons, most squashes and pumpkins, are less susceptible. There are no resistant muskmelons. Two to four weeks mid-spring is the worst time. You could wait and plant late….
Always, do the usuals, to reduce any pest problems. Select disease and pest resistant and tolerant varieties. Keep weed habitat at a minimum, remove cull piles, damaged plants, volunteers. Plant for air circulation and good drainage, water in the AMs when possible, no overhead watering. Give your plants good nutrition. Plant a patch of predator habitat! Use row covers when it makes sense.