May 24, 2023
Alliums: Seed corn maggot activity has significantly slowed down or stopped in the Hudson Valley and plants are recovering from injury. The spring Allium leafminer adult flight has peaked or stopped in the Hudson Valley. Growers using row-cover to protect onions should keep covers on to protect from onion maggot flies that are still active. First generation leek moth caterpillar damage on garlic leaves (windowpane appearance) observed in VT. Economic damage to garlic from leek moth usually only to scapes and not bulb. Next adult flight expected in mid/late June in ENY.
Brassicas: Lots of flea beetle pressure reported over the past week, check under row covers for beetles that may have emerged from soil under the cover. Growers are reporting some plantings with cold/frost injury. Stressed plants may result in premature heading, you can find more information on Spring buttoning in broccoli and cauliflower by clicking here.
Chenopods (Beets, Chard, Spinach): Spinach leafminer activity observed in western MA in chard.
Cucurbits: Lots and lots of green and yellow summer squash going in the ground this week. Take look below at the information on controlling weeds between rows of plastic mulches. The next biggest threat will be Striped Cucumber Beetles, especially on transplanted crops. If you used FarMore treated seed, I would not expect you to get the control of SCB on transplants as you do on direct seeded crops. Why? First, it has a residual of about 3 weeks and most cucurbits when set out are probably at least 3 weeks old if not older. Second, there is a greater chance when watering in the greenhouse that some of the material is flushed right out the bottom of the tray. So, keep an eye on them and apply foliar insecticides as necessary. Aphids, two-spotted spider mites and thrips have been found in the past few weeks on cucumbers growing in high tunnels. Pythium and seedling death observed in northern locations where cucurbit seedlings were planted into cold soil earlier this spring. Contact one of the ENYCHP Vegetable Specialists if you need a management recommendation.
Nightshades: Growers in the Hudson Valley have been planting tomatoes this past week. Low overnight temperatures are expected from Thursday through Saturday morning, growers who have not yet planted may be better off waiting for warmer temperatures next week to set plants into the field.
Tomato brown rugose fruit virus (ToBRFV) has been found this spring on seed of two tomato varieties, Sweet Prince and Brandywise, being sold to commercial growers and gardeners. This emerging virus (first detected in the US in 2018) is considered more serious than others because of the ease of spread when handling infected plants. If you notice any potential symptoms of virus infection in your tomatoes or peppers this season (e.g. mottling and distortion of leaves, discolored fruit, etc.), reach out to the ENYCHP Vegetable Specialists for assistance diagnosing the issue
Overwintered adult Colorado potato beetles observed emerging and laying eggs of first generation of the season.
Corn: Corn around the Capital District is looking much happier now that the weather has warmed up. We are seeing some slight damage on corn from the frost last week, mostly burnt leaves from where they were touching row covers or plastic that was covering it. Remember that the growing point for corn, that is still small, is just below the soil and protected a bit more than what’s exposed. The only other issue that I’m seeing are some weedy fields and I’m not surprised with the lack of moisture to properly activate some herbicides, especially under row covers; so get out there and take a look! If you need to treat, pull the covers, wait a couple days for the corn and the weeds to recover from the shock of being exposed to the elements and follow up with a post emergent herbicide application. If the weeds are still small, most growers have had good luck with Impact or Armezon. However, I have seen it used on grasses that were very tall and saw it stunt and turn it pure white, only to have them come back a few weeks later and start to regrow. The key with these materials is to use them when the grasses are small and make sure you follow the label and add the specific adjuvants and nitrogen sources. I highly recommend that you also add ¼ – ½ lb of atrazine to improve control and residual when using this product. Impact/Armezon will also control quite a few broadleaf weeds as well. Other post emergent materials include Stinger (excellent on ragweed, certain nightshades and Canada thistle. I have also seen it hurt wild buckwheat and Jerusalem artichoke), Accent Q (excellent on annual grasses) and Basagran (contact, excellent on many broadleaves and some annual grasses).
Other/multiple crops:
Weed management between beds covered in plastic mulch can be challenging. ENYCHP vegetable specialist Charles Bornt reviews options for conventional and organic production in this article.
Sporadic cutworm damage on multiple crops seen throughout region. Globular black springtails observed in high tunnels as secondary feeders on plants damaged by other pests. While springtails mainly feed on decaying plant matter, they can become problematic when feeding in high numbers on small seedlings.
This post was compiled by the ENYCHP Vegetable Specialists