Coastal Region

Zack Snipes

• Warmer temperatures and lots of afternoon thunderstorms have really pushed our crops. Up until last week, this was the cleanest year I have seen in terms of disease issues in fields. I expect that to change with warmer temperatures, rain, humidity, and all crops in the reproductive phase.
• Tomatoes are coming in with heavy volumes, as are squash, cukes, cantaloupes, and beans.
• I am starting to get calls and seeing diseases in tomatoes. I have seen some viral disease issues as well as our nemesis, bacterial wilt, start to show up. It is imperative to identify the disease so we can purchase resistant plants next season.

Tomatoes infected with an unknown virus at this point. Identifying the virus by using Clemson’s Lab can help make management decisions for next season.
Zack. Snipes, ©2023, Clemson Extension

Sweet alyssum is a great choice for the beneficial insects in our cropping systems.
Zack Snipes, ©2023, Clemson Extension

Midlands Region

Rob Last

• Strawberry season is rapidly ending. Remember to destroy and clean up fields promptly to aid in sanitation. Warm season cover crops can significantly benefit the soil and nutrient retention.
• Blackberries are coming to harvest with good quality and minimal pest and disease issues. Monitoring for spotted wing drosophila will be very valuable.
• Diamondback moth numbers are rising in leafy greens in the area. Keep rotating insecticides with different modes of action. Utilize the most selective materials to protect the parasitic wasp populations which are active in fields.
• Sweetcorn is looking good and coming to harvest.
• Squash, cucumbers, and zucchini are all coming to market. Watermelons and cantaloupe will be following very soon. Downy mildew is active in all cucurbits. Rotating materials is crucial to prevent resistance.
• Gummy stem blight is also very active in cucurbits
• Tomatoes and peppers look good. Anthracnose is being found in some pepper crops. Tomato hornworms are also active.

Blackberries are starting to come in.
Rob Las, ©2023, Clemson Extension

Pee Dee Region

Bruce McLean

• The weather has been as ideal as it could be over the last few weeks. It looks like it is going to persist for a little while longer, maybe with a little more moisture. Keep an eye on fungal disease development with the increase in moisture. Soil moisture has been a little on the drier side but adequate. Some supplemental irrigation has helped.
• Peaches are being harvested in good volume and quality. Brown rot has been present but not widespread.
• Blueberries and blackberries are looking really good in quality and quantity. We’re squarely in rabbiteye (blueberry) season. Prime Ark 45, Osage, Ouachita, Natchez, Ponca, and Caddo blackberries are in harvest now. Thrips activity is still relatively high in blackberries (in fruit and late flowers). If treating for thrips, remember to look at the PHI of the insecticide and choose one that will work for your harvest intervals.
• Muscadines are looking good. Most vineyards are shaping up to have a great year. Yield may be a little off in some locations due to prior cold injury (where the primary shoot was significantly damaged by freezing temps), thrips activity during bloom, and/or dry calyptra in some vineyards. Dry calyptra (aka stuck cap) is where the calyptra (the “shower cap” covering the ovary) dries prematurely and sticks to the tip of the ovary, preventing pollination from occurring. Conditions that could cause this are weather related – cool, overcast, or rainy conditions during the period of time when the calyptra would release. Initially, the fruit will look as if it has been pollinated. But when cell expansion occurs, the fruitlet will abort. Going through the vineyard with an air blast spray does seem to help if dry calyptra seems to be occurring. Often, the grower does not realize that this has occurred until after bloom when the unpollinated fruit turns loose.
• Strawberries are finally starting to wrap up. There are still a couple of growers picking good quality fruit, but they are planning to be finished in the next few days.
• Sweet corn is starting to be harvested in good volume. Stink bug pressure has been relatively high this season. Hopefully, growers are doing a good job spraying.
• Squash and cucumbers are harvesting good volumes now. Watermelons, cantaloupes, and honeydews are still a little ways off.
• Beans and peas are getting close. Cowpea curculio pressure is fairly high in spots. Bean disease has been relatively low, although that could change with an increase in moisture. Be sure to scout frequently and spray accordingly.
• Tomatoes, peppers, and eggplant are coming into harvest. Okra is looking good after a really slow start.
• Potatoes are still being harvested in good volume and quality.

Dry calyptra on muscadines.
Bruce McLean, ©2023, Clemson Extension

Dry bean trials at the Pee Dee REC.
Bruce McLean, ©2023, Clemson Extension

Upstate Region

Andy Rollins

• The Upstate is picking some peaches at this point but in low volume. Cold-damaged seeds are common with some superficial rots like Rhizopus and others.
• In blueberry, several small farms that are not using conventional fungicides in bloom are suffering from an unchecked fungal organism, mummyberry (Monilina vaccinii-corymbosi). Bill Cline of NCSU has an excellent resource for understanding and controlling the fungus. I recommended the removal of the fruit as much as possible to my small growers that have the issue. This can be achieved by covering them up with mulch or blowing them to the middle of the rows and disking them into the ground.  Heavy rains and temperatures at bloom are thought to have caused the outbreaks this year. Neem sprayed regularly on one of the farms did not control it. Next year these farms will need to make a systemic fungicide application in bloom and utilize protectant fungicides, preferably ahead of major rain events like we have coming this week, to avoid a repeat of this year.
• Japanese beetles are being found doing damage to nearly everything. Some leaf damage doesn’t necessarily merit spray applications, but they can leave an awful taste on harvested fruit of blueberries and strawberries that have no obvious damage from the insect. Tasting your fruit is always an easy way to identify this.

Peaches are coming in but at low volumes in the Upstate.
Andy Rollins, ©2023, Clemson Extension

Shriveled blueberries caused by mummyberry.
Andy Rollins, ©2023, Clemson Extension