Weekly Field Update – 6/28/21

Coastal

Rob Last reports, “Peaches and blackberries are coming to harvest with good quality and volumes.  As yet we are not seeing any issues with spotted winged drosophila. Vigilance will be required as this pest can be troublesome in blackberries. Watermelons and cantaloupes are coming off well. However we are seeing cucurbit downy mildew in watermelons. Spray programs will need to be robust through to the end of harvest to manage the disease. The disease is characterized by brown or yellow spots on the leaves with a Grey’s purple sporulation on the underside of the leaves. Anthracnose is also starting to show up as angular lesions on the stems, leaves and fruit in some fields. Tomatoes and peppers are looking good with some anthracnose fruit rot being seen. There are active spider mites too in some crops. Vigilance and scouting is the order of the day to keep on top of disease and pest issues.”

Zack Snipes reports, “Everything from arugula to zucchini is coming in right now in the Lowcountry.  This next week is usually one of the busiest weeks for us as July 4th approaches. Cucurbit crops are starting to look rough after multiple pickings, disease pressures, and lots of rain.  The tomato crop and watermelon crops are coming off nicely.  I am seeing a good bit of blossom end rot and sunscald in pepper.  Blossom end rot is a calcium deficiency that is usually seen when we have uneven soil moisture levels.  When its hot and there is a heavy crop load, you may need to water more than you think.  In our sandy soils, more frequent, shorter irrigation cycles (45 minutes or so) is better than letting irrigation systems run all night. Sunscald is common when there is poor canopy coverage in the pepper allowing the sun to directly shine on the pepper.  This is usually a result of a root rot or poor fertilization which inhibits a good leaf canopy to develop.” 

Massive blackberries are coming in right now. Photo from Zack Snipes.
Sunscald symptoms on bell pepper. Photo from Zack Snipes.

Pee Dee

Tony Melton reports, “Picking peppers and tomatoes hard. Using a lot of sun protection products on crops. Thrips are really bad on peaches losing about 1/3 of #1s.  Weeds are bad because of all the rain we had when we should have been plowing – especially pickles and sweetpotatoes. Butterbeans and peas are in fair abundance.”

Bruce McLean reports, “Vegetable crops have been growing well, as of late. Sweet corn, peas, tomatoes, peppers, cucumbers, squash, snap beans and zucchini are all being harvested in good volumes. There have been a couple of tomato fields where Southern Blight was seen pretty widespread across the field. Cucurbit Downy Mildew (CDM) is widespread across the Pee Dee, as well as Cowpea Curculio. Growers that are spraying more targeted (management) fungicides for CDM (like Orondis Opti, Gavel, and Ranman) are controlling the disease much better than those applying preventative sprays like Bravo and mancozeb. Seems like everyone is having trouble controlling the Cowpea Curculio, though. Watermelon, cantaloupe and okra should be ready for harvest in about a week. Blueberries are still going pretty strong with good volumes and quality. Blackberries are winding down. Muscadines are coming along, but the crop looks like it may be a bit short this year.”

Cowpea Curculio found feeding inside the shell. Not a sight that the grower wants to see, nor the consumer. Photo from Bruce McLean.
Cowpea Curculio damage is extensive even with 5-day spray intervals. Photo from Bruce McLean.

Upstate

Kerrie Roach reports, “Strawberries are finished and blueberries are king in the upstate. Weather in the region has be varied, and irrigation is key to smaller market producers right now. Spotty showers across the area have left hit & miss spots that may need supplementation. Summer pruning is on the horizon for apple producers… more info to come on a meeting in July.”

Statewide

Dr. Keinath reports, “Cucumber growers should consider adding Presidio back into their fungicide rotations to manage downy mildew. Isolates of downy mildew in Charleston were sensitive to Presidio in 2018, 2019, 2020, and again in 2021. In spring and fall 2020, susceptible slicing cucumber cultivar, Speedway, sprayed with a weekly rotation of Presidio and Bravo had the lowest diseased leaf area and yielded 2.6 times more than nonsprayed cucumbers. Profits were about $3600/acre with Presidio/Bravo compared to $1000/acre with no fungicide calculated after all production costs were accounted. The same efficacy was seen again in spring 2021. It is risky to rely only on two fungicides, Ranman and Orondis Opti, to manage cucumber downy mildew. Adding another fungicide to the rotation will reduce the likelihood that cucurbit downy mildew will become resistant to Ranman or to Orondis.”

Non-sprayed cucumber, June 2020. Photo from Dr. Tony Keinath.
Cucumbers sprayed with Presidio/Bravo, June 2020. Photo from Dr. Tony Keinath.

Weekly Update – 9/14/20

Coastal

Zack Snipes reports, “The talk of the Lowcountry this week is transplant die off.  We see lots and lots of transplant die off and the culprits are usually mole crickets, ants, or cutworms.  Tunneling near the base of the plant is very common when mole crickets are present. Dr. Ayanava Majumdar from Auburn University has done some trials with parasitic nematodes and has seen very good results. For more information on the parasitic nematode visit https://www.arbico-organics.com/category/mole-cricket-controls?gclid=CjwKCAjw19z6BRAYEiwAmo64LSCtnQy6Dd1mx7TLTiNwB0-o7BBZ-XZd54LdBCtYuf2Jm6abINhyKRoChFIQAvD_BwE.  Ants are very common culprits of plant die off as well.  Timely applied baits are the best method for control.  Drench treatments make growers feel better but are not as effective as the baits.  Baits should be applied a few times a year between April and October. A few options to check out are Seduce Bait, Monterey Ant Control Pellets, Come and Get It, and PayBack.”

Transplant die off can occur from cutworms, mole crickets, ants, or disease pathogens.  Be sure to correctly identify before treatments are made.

Pee Dee

Tony Melton reports, “Harvesting sweet potatoes as fast as processing plant can handle them.  Getting good yields.  Army worms are bad!!!  Collards, turnips, and mustard are up and hauling butt.  Dry in some areas and wet in others.  Fall peas and butterbeans are doing well except where damaged by too much rain.  Cucumber for pickles are yielding well except where they were not sprayed for downy mildew.  Watermelons are yielding well where farmers where able to control the gummy stem and drowning during all the rain even then some plants were lost.”

Upstate

Andy Rollins reports, “Fall pepper crop is looking very strong.  Cool milder weather conditions have set us up for a very high yielding and high quality pepper crop.  I found some plants on this farm that died from being waterlogged in the lowest spot of one field.  I also found some fruit with side wall issues.  It was worse in the larger fruited varieties as is normal.  Many times this is misdiagnosed as sunscald but if you examine fully by doing leaf tissue tests you may find out as I did that this is a slight calcium deficiency or imbalance in the plant.  Yes, it is also called blossom end rot in tomato.  In pepper it shows up on the sidewall not just the bottom or blossom end.  Supplying the right amount of calcium is only part of the treatment as normally the problem is more often caused by the plant not being able to move the calcium not that it is missing.  Calcium is a large molecule and requires energy on the plants part to be taken up and distributed.  Careful frequent and regular watering has helped this farm keep this problem to a minimum.”

Pepper fruit with sidewall issues.
Pepper field with waterlogged area causing dieback.