by Ray Bodrey | Jun 29, 2022
A watering tin and gardening gloves at a home garden.
Spending time gardening in the summer months can be difficult, especially in the Florida Panhandle. The brutally high temperatures and sometimes intensive humidity can make gardening seem unbearable. However, for those brave outdoor enthusiasts, there are always things to do around the homestead when it comes to vegetable gardening, landscape shrubs and lawn care.
Warm season vegetable gardening at this point becomes an uphill battle for some crops, with this being peak time for both insect and disease problems to occur. However, if you planted early enough, much of your harvest is probably in the safe zone. Scouting is key to prevent any major pest damage. Be sure to scout several times a week during these hot, summer days.
Shifting gears, the warm season is a good time to take extra special care of plants such as, azaleas and camellias, while they are establishing flower buds for the next bloom. A lack of water, fertilizer and pest detection and prevention can all certainly play a role in the following season’s flower production. Summer annuals always provide quick and easy color. Remember to feed established annuals with a complete fertilizer and remove faded blooms along the way. Water annuals well during hot, dry periods and control major annual pests to insure good production.
Finally, lawn maintenance is a need for many homeowners during this time of year. Almost all highly successful herbicides are no longer recommended at this point, as many will burn the turfgrass at temperatures above 80 degrees Fahrenheit. Depending on the weed pest and type of turfgrass, most likely the best way to control weeds in your lawn is to wait until cooler fall temperature to treat. Keeping good cultural practices this time of year will help in maintaining a healthy lawn and reduce pest pressure. Be sure to water lawns thoroughly when needed by applying one to three quarters of an inch of water weekly, depending on rainfall. Be sure to keep in mind mower height/frequency, as this is critical in keeping your lawn healthy. As stated in the “Mowing Your Florida Lawn” UF/IFAS EDIS publication, mow often enough so that no more than 1/3 of the blade height is removed per mowing. For example, if your St. Augustinegrass lawn is mowed at a height of 4 inches, it should be mowed before it grows to a height above 6 inches. It is important to always leave as much leaf surface as possible so that photosynthesis can occur, particularly in a grass that is subject to environmental or site stresses.
Unfortunately, it is chinch bug time again. Chinch bugs are prone to feed on St. Augustine lawns during hot, dry weather and may cause serious damage if not controlled. Damage usually occurs as a patch with a brown, dead center and yellowish margin. It seems chinch bugs get the blame, and often unjustly, for everything. Consult with your local county extension office to be sure the damage is not due to other reasons.
For more information, please contact your local county extension office.
Supporting information for this article can be found in the UF/IFAS EDIS publications/websites below:
Florida Vegetable Gardening Guide: https://edis.ifas.ufl.edu/publication/VH021
North Florida Gardening Calendar: https://edis.ifas.ufl.edu/publication/ep451#SECTION_7
Lawn Maintenance: https://edis.ifas.ufl.edu/entity/topic/lawn_care
Mowing Your Florida Lawn: https://edis.ifas.ufl.edu/publication/LH028
UF/IFAS Extension is an Equal Opportunity Institution.
by Evan Anderson | Jun 23, 2022
Unlike areas with cooler climates, North Florida’s weather is a bit of a rollercoaster. Where the traditional four seasons allow for one growing season, the panhandle’s temperature changes create two growing seasons – spring and fall. During the winter, temperatures fall too low to keep plants happy, so those who expect to grow tropical plants in Florida may be disappointed. During the summer, the heat and humidity climb to levels that even plants can find stressful! Many of our vegetable crops simply can’t handle the extremes and wither away.
There are a few edible plants we can grow, however, that don’t seem to mind the hot weather. If you simply can’t live without a productive garden during the summer, you might consider trying these:
Cowpeas
Also called Southern peas, black-eyed peas, or field peas, these are known for their ability to produce a crop despite the harshest of conditions. Actually a bean rather than a pea, they take 65 to 125 days to grow to full maturity, depending on variety. Because they are a nitogen-fixing legume, they have also been used as a cover crop.
Malabar Spinach
Malabar Spinach. Photo Credit: James M. Stephens, UF/IFAS
Popular in Asian countries, Malabar spinach is actually a vining plant unrelated to true spinach. It grows quickly and is edible both raw and cooked, though some people may not appreciate its mucilaginous texture. Similar to okra’s sliminess, this quality does make it useful for thickening soups. Malabar spinach may be propagated from seed or by cuttings, which root easily. The plant also produces berries which, while not toxic, have very little flavor and tend to stain whatever they touch.
Okra
A traditional Southern favorite, okra takes the heat and keeps producing. Related to cotton and hibiscus, it grows pods that are ready to harvest after 60-70 days. Seeds have a tough exterior and need to be soaked overnight before planting. Harvest every couple of days at least for best results, as pods that grow too large become tough and fibrous.
Seminole Pumpkin
A Seminole pumpkin. Photo credit: UF/IFAS
Though they may need extra attention paid to them due to their attractiveness to pests, Seminole pumpkins are a great option for a summer planting. Similar to butternut squash, these cucurbits aren’t your traditional carving pumpkin, but they make great eating. Give them plenty of room to spread out in a sunny space. They take 120 days after planting before they’re ready to harvest, and their thick skin allows them to be stored for a long time after.
Sweet Potato
Does well in sandy soil? Check. Doesn’t mind the heat? Check. Sweet potatoes are great for our neck of the woods. Start out with disease-free slips for best results, and pick varieties such as ‘Beauregard’ that do well in our area.
Yardlong Beans
Related to cowpeas, yardlong beans grow on a climbing vine. The beans themselves, as the name suggests, are contained in a pod that can reach 36 inches in length. These can be picked and cooked much like green beans while the pods are still tender.
by Matthew Orwat | Jun 14, 2022
Typical Hollow Heart condition as seen on this Red Lasoda potato. Image Credit: Matthew Orwat, UF/IFAS
One of the most frustrating things about gardening is finding something wrong with a crop that cannot be fixed. I witnessed this last week when checking on a problem with some recently harvested potatoes.
Sometimes potatoes that look perfect on the outside might not be perfect on the inside. Unfortunately, this is the case when potatoes are afflicted by the physiological disorder “hollow heart” or “brown center”.
The disorder that causes hollow heart or brown center in the potato tuber manifests when cells die inside while potatoes are growing too quickly or unevenly, such as when recovering from environmental stress or over fertilization.
Weather extremes during tuber development cause plant stress. Weather conditions that may cause brown center are early season cool nights, which cause soil temperatures to be below the mid-50s for around a week or longer. Soil moisture at 80% or greater may also cause the same brown center symptoms.
Typical Brown Center condition as seen on this Red Lasoda potato. Image Credit: Matthew Orwat, UF/IFAS
Hollow heart is typically caused by swings from low to high soil moisture and overapplication of nitrogen. To mitigate this condition, consistent irrigation practices and spit fertilizer applications have been shown to be effective.
Additionally, if hollow heart or brown center is a typical problem for a given growing area, selection of cultivars that are less susceptible to this condition is beneficial, since there is quite a bit of variation among cultivars / varieties.
The final message is one of good news, if brown center or hollow heart is noticed at potato harvest this year, there are steps that can be taken to mitigate this issue for future growing seasons.
For more information, please check out the reference for this article, UF/IFAS publication HS945 “Potato Physiological Disorders—Brown Center and Hollow Heart”
by Matt Lollar | Jun 9, 2022
This article was written by Kacey Aukema, University of Florida/IFAS Extension – Walton County.
I recently met with a home gardener who brought in tomato plants showing strange symptoms on the leaves. Together we puzzled over the odd leaf-curling symptoms that were affecting their tomato beds, but not other areas of the garden. Upon further investigation it was revealed that hay, used as mulch, had recently been spread around the tomatoes, but not in other areas of the garden. It quickly became apparent that the symptoms were likely related to herbicide residual on the hay that was used. The herbicide aminopyralid was the potential culprit. In this case the residual herbicide was not enough to outright kill the growing tomato plants. However, it was interfering with their growth and development and is a cautionary tale reminding us how important careful sourcing of hay used in mulch or compost can be.
What is aminopyralid and how does residual herbicide affect non-target plants through mulch, compost, etc.?
Aminopyralid is a herbicide active ingredient found in several popular pasture products such as GrazonNext™, Milestone™, Chapparral™ and similar products. This and other similar chemicals have residual activity and can be retained in plant tissues, animal manure, and soil, which makes them a very useful for controlling certain troublesome broadleaf weeds in grass pastures for an extended period of time. Unfortunately, this residual activity increases the potential for causing trouble in vegetables or other crops when hay or animal manure from aminopyralid treated pastures is mistakenly used for mulch, compost, etc. In Florida, aminopyralid containing pasture herbicides are often used as the “go to” for control of hard to control weeds like horsenettle and tropical soda apple which are potentially toxic to livestock. Tomatoes, potatoes, and eggplant are in the same genus (Solanum) as those weeds and are therefore very susceptible to this herbicide as are many other vegetable and other broadleaf crops.
Residual aminopyralid damage on a tomato plant. Photo Credit: Kacey Aukema, University of Florida/IFAS Extension – Walton County
How can I know if hay is safe to be used for mulch or compost?
Before acquiring hay to be used as mulch or to compost for vegetable beds, be sure to ask if the hay is free of herbicides with residual activity. Find out what was sprayed on the field in the last two seasons before the hay was harvested. Given that hay destined to be used as mulch or compost is usually old and spoiled, management history of a particular hay bale is likely to be hard to pin down. Do not trust hay to be used for mulch or compost in vegetable beds if prior spray management details are unknown. Also consider that well-stored hay may retain residual herbicide better and for a longer period of time than weathered hay, as the active ingredient is less subject to weathering and biological breakdown.
Those who use broadleaf herbicide products with residual activity such as those containing aminopyralid are subject to follow herbicide label guidelines. For instance, supplemental labeling of GrazonNext HL™ (including FL, AL, and GA) indicates that hay/straw from fields sprayed in the past 18 months should not be used for compost, mulch, or mushroom spawn. When in doubt refer to the label of the particular herbicide product used on hay you purchase for any restrictions and/or reach out to your local county extension agent if you have questions about a specific herbicide product. Relevant use restrictions and considerations like in this example should be conveyed between hay producer and buyer.
Perhaps you already have some hay for mulch/compost with an unclear management history, or you would like to double-check and be sure that it is safe. How could one test it to see if it was safe to use? There is a test called a “bioassay”, conducted by growing susceptible plant seedlings like tomatoes or beans in small pots with the hay/compost/mulch in question incorporated into the potting soil. Then, the test plants can be observed to see if any herbicide symptoms develop to know whether the material is safe to use, before using the hay over a larger area or garden where there would be more risk. For more information on how to conduct a bioassay see: Herbicide Residues, in Manure, Compost, or Hay. Similar in-field bioassays are also recommended when rotating areas out of pasture and into other crops when pasture herbicides with residual activity were used. If susceptible crops like peanuts are grown in areas where such herbicides were used in the recent past they can be damaged, as in this case in an older Panhandle Agriculture Newsletter post.
When used according to label instructions, herbicides with residual activity are very useful for control of broad-leafed weeds in pasture and hay fields and may reduce the spread weeds through seed coming in on purchased hay. However, problems can emerge when hay from fields treated with these products change hands without the use restrictions and considerations being adequately explained. Therefore, caution should be taken by both producer and buyer to avoid damaging sensitive crops when hay or livestock manure are used for mulch or compost.
by Matthew Orwat | Jun 9, 2022
Snap Bean leaf with common bacterial spot – Image Credit Matthew Orwat, UF/IFAS Extension
As snap bean season is winding down and daytime temperatures regularly approach the lower 90s, common bacterial blight is making its presence known. In March or April, when snap bean plants are young and full of fresh growth, vegetable gardeners would never guess that their leafy plants could turn spotty and ugly during harvest time.
That is exactly what happens when daytime temperatures steadily remain in the mid-80s and low-90s, and nighttime temperatures are in the lower 70s. The perfect storm for this bacterial disease occurs when these temperatures combine with afternoon and evening showers, creating sticky, humid nights perfect for the proliferation of the causal agent, Xanthomonas campestris pv. Phaseoli.
Common bacterial blight begins showing up on older leaves first and then slowly spreads to younger growth and pods. If plants are left untreated, disease progression will continue if rainy nights and warm daytime temperatures continue. If weather conditions are consistently dry, daytime temperatures are above 90 and overhead irrigation is limited to mornings or eliminated, the blight will stop progressing to new growth. This disease may also be transmitted by insects.
Note the brown, water-soaked spots on the underside of this leaf, typical of a bacterial infection – Image Credit Matthew Orwat, UF/IFAS Extension
If conditions favorable to common bacterial blight exist, preventative sprays of copper fungicide will work to
Snap Bean leaf with common bacterial spot – Closeup – Image Credit Matthew Orwat, UF/IFAS Extension
reduce infection and damage to crop, but there is no product to cure what has already been infected.
One of the best techniques available to manage common bacterial blight in beans is to rotate crops regularly so that legumes are not grown on the same ground year after year. This is easily accomplished in a diverse home garden with different raised beds or garden plots.
To learn more about common bacterial blight of bean follow these links to the NFREC Plant Pathology U-Scout page or read IFAS Extension PUBLICATION #PP-62
