Field Update – 6/29/20

Coastal

Rob Last reports, “In our area crops are generally looking good with watermelons and cantaloupes coming to harvest.  From a pest perspective, we are finding some early pickleworm and melon worm damage occurring. In addition, cucumber beetles and squash bugs remain active. Cucurbit downy mildew is being found in the area and as such protectant fungicide applications remain viable options. If in doubt scout.”

Zack Snipes reports, “Last week was full of heavy rain and heat. It finally feels like June.  Crops are either going one of two ways right now:  they either look great or they are succumbing to disease. Tomatoes are picking great and I’ve seen some really nice watermelons finish up this week. Peppers are loving this heat but I have seen an uptick in bacterial leaf spot (BLS) in the crop. Keep up with spray programs (copper and Manzate) for BLS in pepper. Tomatoes are also starting to look rough with all the heat and rain. If your tomato crop dies, please identify the culprit so we can better manage it next year. Soilborne diseases such as bacterial wilt and southern blight will not go away next year. I will be more than happy to work with folks on crop planning, cover crops, and rotation on their farms so we can avoid crop failures.

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A quick cut of the stem of a wilting plant and a dip into water can help to positively identify Bacterial Wilt in tomato. The presence of the pathogen will yield a clear to white ooze coming from the plant after a few minutes in the water. Photo from Zack Snipes.

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Bacterial Leaf Spot is spreading in pepper due to the heavy rains and increased heat. Photo from Zack Snipes.

Midlands

Justin Ballew reports, “We finally got some widespread rain mid-week and it has rained in places most days since. Some areas received enough rain to cause temporary flooding in lower-lying fields. Remember, according to produce safety guidelines, any produce that was flooded may not be harvested. We should expect diseases to worsen in the coming weeks. Powdery mildew in cucurbits and bacterial spot in tomatoes has certainly increased in the past week. Crops are still developing very rapidly and we are picking lots of squash, zucchini, cucumbers, tomatoes, eggplant, sweetcorn, greens, beans, etc.”

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This field of cucumbers was temporarily flooded by the heavy rain last week. Photo from Justin Ballew

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A crew picking squash in Lexington. Squash and zucchini are growing like wildfire in the midlands. Photo from Justin Ballew.

Pee Dee

Tony Melton reports, “Raining almost every day some storms causing downed trees.   Root rot bad applying a lot of potassium phosphide. A few strawberry growers still picking around rains. Downy mildew bad but Ranman and Orondis are doing a good job of control. Peas are maturing and will not be too long until harvest. We need to hurry to get the second crop planted on the same land. Still planting sweet potatoes. Okra and tomatoes just started to bare. Southern stem blight is bad and we’re spraying Fontelis. Some first crop butterbeans are being harvested.”

Field Update: 6/22/20

Coastal

Zack Snipes reports, “A week of unseasonably mild temperatures and damp conditions slowed things down a bit. The warmer weather this past weekend and this week should put things in gear again. Starting to find some armyworms on smaller farms particularly the southern armyworm. Tomato spotted wilt virus has been showing up on tomato fruit in the Lowcountry. The disease is vectored by thrips. Early and mid-season symptoms include stunted plants that will never make fruit and brown/purple mottling on the leaves. Some plants are asymptomatic, meaning that they show no symptoms of the disease. I have been finding plants that are asymptomatic until they fruit and then symptoms appear on the fruit. Using tomato varieties that are resistant to the disease is the best management technique. The Crop Handbook has a list of varieties that have resistance. Using silver reflective mulch will also help with disease management as the mulch will repel thrips which vector the disease.”

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Characteristic symptoms of Tomato Spotted Wilt Virus on tomato fruit. Photo from Zack Snipes.

Midlands

Justin Ballew reports, “Last week was very cool and cloudy. Though there was a decent chance of rain most days, we got very little and it remains dry in the midlands. The cool, cloudy weather really slowed things down and growers weren’t able to harvest crops as often as usual. Since there was little sunlight to dry up the dew each morning, powdery mildew really started showing up in cucurbits. It warmed back up over the weekend and plants seem to be growing faster already. Downy mildew still has not shown up here. Keep scouting and applying protective fungicides.”

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Powdery mildew growing on acorn squash foliage. Photo from Justin Ballew.

Lalo Toledo reports, “Squash bugs are active and laying eggs. Please scout for eggs on the underside of leaves and spray as soon as signs are visible. Squash bug nymphs, are gray and have black legs. Refer to the vegetable handbook for proper chemical control. Downy Mildew has been diagnosed in Orangeburg County. Please refer to the vegetable handbook regarding fungicide applications. It’s recommended to stay on a fungicide schedule and to apply protectants even before we start seeing symptoms.”

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Squash bug eggs laid on the underside of a squash leaf. Photo from Lalo Toledo.

Pee Dee

Tony Melton reports, “Cool temperatures making everything late especially peas and okra. Most sweet potatoes are planted. Things are drying out quickly with the heat.”

Asian Longhorned Beetle Found in SC

From Clemson Forest Health and Invasive Species Specialist Dave Coyle.

The Asian longhorned beetle has been found near Hollywood, SC (Charleston County).  This invasive tree pest primarily attacks maples (especially red maple) but also elms, willows, and birches. Clemson Regulatory Services, Clemson Extension, and USDA APHIS need your help in detecting this beetle in the Lowcountry. Adults are large (up to 1 ½” long) black beetles with white spots, black and white striped antennae, and bluish feet. Signs of ALB include large, pencil-sized holes on trees and bleeding from wounds on the trunk. There are several native beetles that look similar to ALB – please check out the fact sheets on the HGIC page. If you think you’ve seen ALB, please contact the Clemson Department of Plant Industry at invasives@clemson.edu or by calling 864-646-2140.

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Adult Asian longhorned beetle.

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Following pupation, the adult ALB bores its way out of the tree leaving these large holes in the trunk.

Clemson HGIC ALB Fact Sheet

Clemson HGIC ALB Blog Post

Clemson Regulatory Services Pest Alert

Video from Don’t Move Firewood on ALB

Don’t Move Firewood Program

Dave’s Twitter (where he puts the most up-to-date info)

Downy Mildew Found on Watermelon in SC

Downy mildew was found yesterday, June 17, 2020, in one watermelon field in Bamberg County, South Carolina. All growers should immediately spray watermelon with Ranman, Revus, or Gavel to protect their crops from downy mildew. In addition to direct yield loss, loss of vine cover can expose fruit to sunburn (when the sun comes out again). Growers who find downy mildew in a field should apply Orondis Ultra or Orondis Opti in a weekly rotation with Ranman or Gavel. For more information on downy mildew, see the updated Cucurbit Downy Mildew Management for 2020.

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Downy mildew symptoms on watermelon foliage. Photo from Dr. Tony Keinath.

Field Update – 6/15/20

Statewide

The video below is from Vegetable Weed Specialist Matt Cutulle. It shows a flame weeder attachment killing weeds around the edges of a field. The person walking behind the tractor is using a flame weeder with a propane tank on his back. These are good options for weed control in organic fields.

Coastal

Zack Snipes reports, “It’s the time of year when crops are starting to look ugly.  We are in the middle of tomato harvest and it seems to be a pretty good crop this year.  Bacterial spot is starting to spread up the plants due to a heavy fruit set, perfect weather, the inability to spray, and constant handling by pickers. Keep up with spray programs as the last few weeks of development are critical to size and taste.  Rabbiteye blueberries are coming in strong right now and look really good with the occasional berry having Exobasidum. Stink bug pressure has been very high this year and I’m seeing damage on a multitude of crops.”

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It is critical to know the difference between Southern Blight and Bacterial wilt when managing tomato diseases.  Southern Blight will have a white fungal mat with small “BBs” on the stem. Photo from Zack Snipes.

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Bacterial wilt shows up in the same fields year after year. Photo from Zack Snipes.

Rob Last reports, “In our area, we are seeing some good quality watermelons and cantaloupes coming to harvest.  We are seeing some manganese toxicity related to low pH in both crops.  Also given the sporadic storms we have seen leaf potassium levels have been lower than ideal.  It would be recommended to monitor tissue nutrient levels and adjust fertilizer applications accordingly.”

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Manganese toxicity on cantaloupe leaves appears as round, tiny, tan spots, sometimes with a yellow halo.  This symptom can be misdiagnosed as early downy mildew. Foliar analysis can be used to diagnose Mn toxicity. Photo from Dr. Tony Keinath.

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 On the leaf underside, the halo appears water-soaked (“greasy”). This symptom can be misdiagnosed as early downy mildew. Foliar analysis can be used to diagnose Mn toxicity. Photo from Dr. Tony Keinath.

Midlands

Justin Ballew reports, “We got a little much-needed rain last week. Crops are developing quickly and growers have started harvesting the oldest planted sweet corn as well as squash, zucchini, cucumbers, beans, and what’s left of spring brassicas. Cucurbit downy mildew has not yet been found in the midlands, but it probably won’t be long. Keep applying preventative fungicides.”

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Zucchini almost ready to be picked. Photo from Justin Ballew.

Sarah Scott reports, “Peach season is in full swing. Bacteriosis and brown rot continue to show up in many fields. Warm temperatures during an extended bloom period as well as rain and cold at critical times in the early season are likely the culprits for these issues.”

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Bacteriosis on ripening peach. Photo from Sarah Scott.

Pee Dee

Bruce McLean reports, “Cucumbers are being harvested in good numbers. Squash and zucchini yields are increasing. Sweet corn will be ready to begin harvest in a few days. Disease pressure is increasing in cucumbers, primarily Cucurbit Downy Mildew (CDM). CDM has caused significant damage and severely reduced the crop in two locations. Forecasted rains for the next 7-10 days will make it extremely difficult to spray fungicides (as well as applying insecticides, herbicides, and fertilizer). Fruit crops are being negatively impacted by the weather, as well. Reduced fruit quality is caused by increased disease pressure and wet field conditions. And, the forecast over the next 7-10 days is for more rain.”

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Checkerboard pattern indicative of Cucurbit Downy Mildew on cucumbers. Photo from Bruce McLean.

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Purplish-brown sporulation on the underside of cucumber leaves confirms that it is Cucurbit Downy Mildew. Photo from Bruce McLean.

Tony Melton reports, “Cucurbit downy mildew is increasing rapidly with the rain, glad we started spraying Ranman or Orondis 2 weeks ago. With the rain, ponds have returned to our fields. As one of my vegetable farmers said “Not a good year to be in the Pee Dee vegetable business.” Hundreds of acres of beans, squash, cucurbits, and peas have drowned. Farmers are probably tired of me saying “Potassium Phosphide will help.” Regretfully, on brassicas, the yellowed margined beetle has become established in the Pee Dee, and downy mildew is awful. However, sweet potatoes are growing like a weed (its close kin morning glories).”

SC DPR Releases Statement on Recent Dicamba Cancellations

This week, the SC Department of Pesticide Regulation (DPR) released a statement regarding the EPA’s cancellation of three dicamba products following a Federal Court of Appeals decision to vacate their registrations. The three products (Xtendimax, Engenia, and FeXapan), labeled for use with tolerant soybean and cotton varieties, have been a hot button issue since their initial registration in 2016. Concerns of off-target damage due to drift and volatilization have been at the center of this contention.

According to DPR, “Pesticide dealers in South Carolina who have existing stock of these products should stop all sales immediately and contact their dealer representative to facilitate a return to the registrant or other legal disposal. The EPA final cancellation order allows for Commercial and Private applicators who have possession of existing stock of these products to lawfully use them until Friday, July 31, 2020. After this date no legal uses of these products will be permitted and existing stock must be disposed of in a legal manner.”

Read the full DPR news release here.

Read the full EPA cancellation order here.

The Court of Appeals ruling and subsequent cancellations do not affect other formulations of dicamba.

Field Update – 6/8/20 (Downy Mildew Arrives in SC)

Statewide

Downy mildew was found in Charleston, SC late last week on cucumbers. This is the first confirmed report of the 2020 season. If not already doing so, all cucumber and canteloupe growers should begin applying protective fungicides to help prevent or manage downy mildew. Ranman tank-mixed with a protectant such as chlorothalonil, mancozeb, or Zampro is a good option for protecting plants prior to symptom development. For more info, see Dr. Tony Keinath’s CDM Management publication.

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Downy mildew symptoms on the top side of a cucumber leaf. Note that the spots are angular in shape and are delineated by the veins in the leaf. Photo from Justin Ballew.

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Dark-colored downy mildew spores developing on the underside of a cucumber leaf. Photo from Justin Ballew.

Coastal

Zack Snipes reports, “It is a very busy time out in the fields. Every crop is coming in right now and folks are busting it to get crops out and keep the remaining crops healthy.  Keeping up with fertility, fungicide, insecticide, and herbicide programs can really help with the bottom line as now is when our crops need a little help. With the mild temperatures and cloudy, wet days last week, I saw some diseases appear and spread.  On tomato, I am finding increased bacterial spot that is starting to make plants turn yellow. This will cause a yield drag and the spots can be found on the fruit if the infection is not slowed down. Downy mildew was found in cucumber last week so be sure to be proactive and keep an eye out for that. I saw some other cucurbit diseases last week including gummy stem blight and Alternaria. The stink bug population has also increased in the past week or so with some damage showing up on tomato. Please refer to the 2020 Southeastern Crop Handbook for details on management programs for insects, diseases, and weeds.”

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Bacterial spot is increasing causing yellowing of the plants. Bacterial spot can reduce yields and develop spots on the fruit. Photo from Zack Snipes.

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Downy mildew found in cucumbers last week. Photo from Zack Snipes.

Midlands

Justin Ballew reports, “Last week was warmer and actually a little dry. Lots of irrigation has been running. Crops are progressing quickly. Strawberries are mostly done now. The silks on the earliest planted sweetcorn are browning and harvest isn’t far off. Tomatoes, peppers, eggplant, squash, beans, and cucumbers are also progressing well. Downy mildew has been found in the state, so be sure to start preventative fungicide sprays on cucumbers.  Let us know if you’d like help scouting fields for downy.  Collards, cabbage, and kale are still being harvested and are looking good.”

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Silks are turning brown on the earliest sweet corn plantings. Photo from Justin Ballew.

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Tomatoes are developing well. It won’t be long before harvest starts. Photo from Justin Ballew.

Lalo Toledo reports, “Downy Mildew has been diagnosed in Charleston County. However, Downy Mildew has not been found in Orangeburg county.  Please be advised that it is a matter of time before we start seeing symptoms. Please refer to the vegetable handbook regarding fungicide applications. It’s recommended to stay on a Fungicide schedule and to apply protectants even before we start seeing symptoms. Bacterial Wilt on tomatoes is present in many fields in Orangeburg county. Please contact your local extension office for proper recommendations.”

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It’s only a matter of time before downy mildew shows up in cucurbits in Orangeburg County. Photo form Lalo Toledo.

Pee Dee

Bruce McLean reports, “Field conditions really improved this past week. Cucumbers are being harvested in good volumes. Overall, quality is good. Downy mildew is starting to show up in cucumber fields that were affected by recent heavy rains. Squash and zucchini are beginning to be harvested, as well. Snap beans and southern peas are flowering heavily. Some acreage of snap beans were lost due to ponding caused by recent heavy rains. Many fields of sweet corn are tasseling well and beginning to silk. Watermelon, cantaloupe, and peppers are growing very well. Blueberry quality is beginning to improve. Much of the rain-damaged fruit has been removed. Currently, the blueberry crop looks good. Muscadine fruit set is good, but thrips and aphid activity is high, which could cause problems in yield. Scouting is necessary to determine pest presence and necessary insecticide application.”

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Downy mildew really showing up in rain-stressed fields. Photo from Bruce McLean.

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Snap beans affected by ponded water from recent heavy rains. Photo from Bruce McLean.

Tony Melton reports, “Some areas got 10 inches of rain in one day. Hundreds of acres of beans and cucumbers are drowned. Cucurbit downy mildew is here on cucumbers. Weeds are awful.”

Upstate

Kerrie Roach reports, “With heavy rains a few weeks ago, high humidity and heat this past week, we are seeing some disease problems pop up across the board… make sure you are following prevention practices that fit into your growing style. Conventional, organic, or somewhere in between, all growers should be managing disease through preventative measures. Crop rotation is arguably one of the most important strategies in an Integrated Pest Management (IPM) program. If you’re a grower that hasn’t moved crops around within your site in years, now is that time!”

Andy Rollins reports finding black knot of plum. “Prune out these galled up branches as quickly as possible before they begin to sporulate. I also recommend sterilizing or at least sanitizing the pruners as much as is possible between cuts.  Treat with 2 lbs of Captan foliarly as soon as possible after pruning to try and keep those wounds free from other problems.  This problem can come in on the purchased trees, but can also come in from wild cherry trees or wild plum surrounding the orchard.  It is always a good thing to kill any and all wild cherry and plum trees directly adjacent to a commercial orchard.  Penn State has some good information here.”

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Black knot on plum branches should be pruned out before sporulation begins. Photo from Andy Rollins.

Field Update – 6/1/20

Statewide

Dr. Matt Cutulle reports, “Yellow nutsedge is one of the more problematic weeds we deal with and we are approaching peak nutsedge season with the heat and all the rain we have been getting. Post herbicide options are limited in most vegetable crops. However, if growing sweet corn you may have the option to combine a good (Basagran) Post nutsedge herbicide with an average Post nutsedge herbicide (Callisto) to provide excellent control of yellow nutsedge. Please consult your seed company regarding whether a specific variety is expected to be tolerant to post-emergent applications. The majority of sweet corn is tolerant to PRE application of Callisto.”

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Coastal

Zack Snipes reports, “We had some heavy rains in places last week, but everything seems to be drying out. It seems that every crop is coming in right now from basil to zucchini so everyone is busy out in the fields. Now is the time, when things are busy, that insects and diseases thrive. Perhaps a weekly fungicide application is skipped and a small issue turns into a disease or insect outbreak. Stay on your scouting, IPM, and spray programs as much as possible.”

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Spring collards left in the field and forgotten but are not forgotten by the insects. Destroying this crop residue now will decrease the fall insect pressure. Photo from Zack Snipes,

Midlands

Justin Ballew reports, “Lots more rain last week, but the weekend was nice and allowed for a lot of the excess water to dry up. It doesn’t take long in our sandy soil. Lots of water damaged strawberries along with Botrytis and either Rhizopus or Mucor rot (possibly both). Some growers have wrapped up picking and others will be wrapping up soon. We’ve had a decent picking season here in the midlands and reported sales were very good. Other crops like tomatoes, peppers, sweet corn, and beans are growing fast and looking good. Stay on top of disease programs right now.”

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Squash is growing fast and it won’t take long for this little one to be ready to harvest. Photo from Justin Ballew.

Sarah Scott reports, “Peach harvest is going strong throughout the Ridge. Warmer, wet weather has been on the increase which could give way to some emerging pest and disease issues. Brown rot is showing up in some orchards. Bacterial spot is also heavy in areas. Continue spray programs following the Southeastern Peach,  Nectarine and Plum Pest Management Guide. Summer crops and looking good with some powdery mildew showing up in squash. Increased diamondback moth caterpillars in broccoli.”

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Phytotoxicity from insecticide sprayer left running while turning the corner of the row. Photo from Sarah Scott.

Pee Dee

Bruce McLean reports, “Strawberry season has (for-the-most-part) come to an end. Heavy rains for the last two weeks was the primary reason. Excess moisture has damaged blueberries and caused a somewhat early harvest of potatoes. Many fields are too wet to make pesticide applications. Disease, insect, and weed pressure is getting rather heavy in spots. Fertility is a major concern, as well. Much of the pre-plant fertilizer applied early in the season is likely leached out/moved in the soil profile, and fields are too wet to apply fertilizer. Drier conditions are desperately needed to improve field and crop conditions.”

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Heavy blooming and fruit set on Carlos muscadines. Photo from Bruce McLean.

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Heavy persistent rains causing blueberry fruit to split. Photo from Bruce McLean.

Tony Melton reports, “I am thinking about becoming an aquaculture agent to help farmers stock all these ponds from the rain in their fields. I am recommending folks to spray phosphide products to perk-up the crops and help with all the root rot – even if it has to be done with an airplane. Thrips, stink bugs, and false cinch bugs are awful this spring. We have Pythium growing in sweet potato transplant beds and on cucumbers from the heat and rain. Everything from cucumbers to peppers are baring early because of the stress of the wind earlier in the spring. We are adding extra nitrogen to everything because of the leaching rains. Weeds are taking over the world.”

Field Update – 5/26/20

Statewide

Dr. Tony Keinath reports, “Powdery mildew was found late last week on watermelon at the Coastal REC, Charleston. All watermelon growers should look at the photo below to be sure they can identify powdery mildew in the early stages. The spots are pale yellow, and, unlike squash, may not have white powdery growth under the spot on the bottom of the leaf. See Powdery Mildew on Watermelon Land-Grant Press 1019 for spray recommendations (https://lgpress.clemson.edu/publication/powdery-mildew-on-watermelon/).”

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Light yellow spots on watermelon leaf from powdery mildew. Photo from Dr. Tony Keinath.

Coastal

Zack Snipes reports, “I saw a good bit of powdery mildew last week on all cucurbit crops. I have had several questions this spring about injury to watermelon. I think the strong winds, sand, and spraying damaged the crowns of melons. They are growing out of it now but have had some folks concerned. Bacterial wilt is showing up in tomato as temperatures climb and fruit is loading up in the crop. Keep up with scouting for insects and diseases. Overall things look great.”

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Crown injury on watermelon due to high winds and sandblasting. Photo from Zack Snipes.

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Conditions have been perfect for the development of powdery mildew on cucurbit crops. Photo from Zack Snipes.

Rob Last reports, “Watermelons generally look very good with great color and potential with early fruit set occurring.  Fusarium wilt is active at low levels in some places, as to be expected in areas of impaired drainage.  Also, I observed a little hail damage to watermelons and cantaloupe in Bamberg County.

Midlands

Justin Ballew reports, “It’s been raining a lot in the Midlands, but we really needed some rain. I’ve had almost 6.5 inches at my house since last Monday (5/18). This has slowed down strawberry picking and we have a ton of water damaged berries. Botrytis is loving all the moisture. Most fields look like they will keep producing for a few more weeks,  just stay on top of fungicide programs. The moisture and warm temperatures have most other crops growing rapidly and looking good. Keep an eye out for disease.

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These strawberries sitting in water will be damaged and need to be removed from the field before botrytis begins to develop. Photo from Justin Ballew

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Tomatoes are loving the warm weather. Photo from Justin Ballew.

Pee Dee

Tony Melton reports, “Anyone have an ark?  Many fields are flooded. Nutrients are washing away and strawberries are water-soaked.  Some strawberry farmers have stopped picking.  Water-logged soil causing crops to stop growing and we have to rely on airplanes to spray crops.  Weeds are enjoying the rain.”

Bruce McLean reports, “Last week was rainy in most locations, and this week looks like more of the same. Disease pressure is elevated due to excessive moisture. Seeing gummy stem blight showing up in cucumbers and bacterial spot in tomatoes. Thrips pressure had been high going into last week (especially on beans, peas, and cucumbers), and could still be high in the few locations that missed the heavy rains. But everywhere else, the heavy rains likely reduced thrips activity. Strawberries are finishing up. Heavy rains damaged most of the remaining red fruit. Blueberry harvest is starting to increase. Prior to rains, fruit was looking really good. The excess moisture did cause some fruit splitting, but no long term damage to the crop. Haven’t seen much thrips activity in muscadines yet, but now concerned with increased problems with calyptra release, a condition known as stuck cap. It’s a little early to tell, but could reduce yields.

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Thrips damage to southern peas. Photo from Bruce McLean.

Upstate

Kerrie Roach reports, “We are building the ark to send down to Tony in the Pee Dee!  Lots of flooded fields last week (and today) with many places seeing 4-6 inches of rain over 3 days. Strawberry growers halted picking and worked around the rains. Vegetable producers are replanting washed out crops and draining fields.  Peaches and apples continue to be on track for a good season. Localized hail damage is showing up on apples in Mountain Rest from one of the storms a few weeks ago.”

Field Update – 5/18/20

Statewide

Dr. Tony Keinath reports, “With the cooler-than-normal spring weather, two cool-season pathogens also may be active longer than normal. Downy mildew on brassicas, especially kale and collard, mainly affects the lower leaves. Sometimes it will move up onto the larger leaves in the middle of the plant. With a hand lens, you can see white mildew growth in lesions on the bottom of the leaves. In my spring 2020 trial, Presidio, potassium phosphite, and Zampro rotated with potassium phosphite worked well. Organic growers can use Badge X2 copper, which also performed well.

Fusarium oxysporum f. sp. niveum, the soilborne fungus that attacks watermelon, infects roots when soil temperatures are below 82F. At Coastal REC, I am still seeing new plants showing wilt symptoms. Remember that all control measures, and I want to stress all of them, must be applied before or at transplanting. There is nothing that can be done at this stage of crop growth. It is too late to apply fungicides, which will be a waste of money.”

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Tiny dark flecks of downy mildew on the bottom of ‘Blue Dwarf’ kale. Photo from Dr. Tony Keinath.

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Sporulation of downy mildew on the underside of ‘Tiger’ collard. Photo from Dr. Tony Keinath.

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Wilting and yellowing of lower leaves due to Fusarium wilt on watermelon 6 weeks after transplanting. Photo from Dr. Tony Keinath.

Coastal

Zack Snipes reports, “Things are coming along in the Lowcountry.  It has been very windy and I’ve had several farmers tell me that crops are using more water now because of the wind than if it were hot and humid.  Squash, zucchini, cukes, potatoes, and greens are coming off in good volume right now. Tomatoes are just a few weeks away and are in the sizing up stages right now. I have not seen any major pests or diseases as of late.  The conditions are ripe for the development of Powdery Mildew so be on the lookout when scouting watermelon, squash, brassica, and tomato.”

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Tomatoes are looking good and are just a few short weeks away. Photo from Zack Snipes.

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Powdery mildew on the shaded side of a collard leaf. Photo from Zack Snipes.

Midlands

Justin Ballew reports, “It’s dry in the midlands. It’s been great because we haven’t seen much disease lately (especially on strawberries), but we need some rain. The forecast looks like we may get some this week. Strawberries are still yielding fairly well, though we’re starting to see fewer blooms. Fruit size is getting smaller, but taste has still been great. The first few plantings of sweet corn are tasseling now. Brassicas are still growing well, though there is some black rot out there.  Tomatoes, peppers, and cucurbits have been growing fast the last few days also.”

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The earliest plantings of sweet corn are tasseling. Photo from Justin Ballew.

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Black rot symptoms on the margins of cabbage leaves. Photo from Justin Ballew.

Sarah Scott reports, “Peach season is here! Picking several early varieties now and running packing lines. The crop looks good for this season. Bacteriosis started to show up on leaves and fruit in fields. Still picking strawberries. Summer crops like bell pepper and squash are progressing nicely.”

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Phomopsis or twig blight in a peach orchard. Lesions on twigs cause dieback, gumosis and curling at tips. Remove damaged wood and burn. Photo from Sarah Scott.

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Twig dieback from Phomopsis twig blight. Photo from Sarah Scott.

Lalo Toledo reports, “Cool temperatures have slowed down the growth of many vegetables, but most vegetable plants are looking great. Please be aware of possible diseases coming in this week. Wet and hot conditions will be conducive for pests and diseases. Please spray accordingly and scout every two days, if possible.”

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Grasshopper damage on eggplant. Photo from Lalo Toledo.

Pee Dee

Tony Melton reports, “Hail has destroyed at least 10 A squash, 200 A peaches, 30 A strawberries, 8 A blackberries, many acres of field corn, tobacco, rye, and wheat.  Damaged another 35 A strawberries, 300 A peaches.  Thank goodness that the wind has let up for a while and temperatures have risen on tomatoes, peppers, peas, beans, and sweet potatoes.  Thrips have been awful and imidacloprid is only partially controlling them. If labeled use dimethoate, acephate, etc.   More herbicide damage than usual this year because of cool temperatures and wind, even on labeled crops and drift to non-labeled crops has been awful.”

Upstate

Kerrie Roach reports, “With a week of good growing conditions, things are looking great in the Upstate for fruit & vegetable producers. In higher elevations, there were some losses of young tender plants during isolated frost events early last week. With rains expected most of this coming week, things should start to really push for our market vegetable growers. Peaches and apples are on track for a good season.