Ripening thornless blackberries. Photo credit: Mary Salinas, UF/IFAS Extension.
To everyone’s delight, the blackberries are ripening in the Santa Rosa County Extension demonstration garden. The blackberry patch is a reliable perennial that continues to provide fresh berries year after year. Before you decide against them because you don’t want a thorny and painful hazard in your landscape, remember that there are thornless blackberry cultivars with fruit just as tasty as the old-fashioned thorny blackberry varieties. However, it is important to take care and make sure that the variety or cultivar you choose is adapted to our Florida climate and chill hours.
Blackberries bloom and produce fruit on last year’s canes. This year’s growth (the bright green shoot in the front center) will produce next year. Photo credit: Mary Salinas, UF/IFAS Extension.
You can choose a blackberry variety from your local nursery or propagate some plants from a favorite blackberry grown by a friend or neighbor (with permission, of course). Methods of propagation include stem cuttings, root cuttings, tip layering and removing the suckers that arise from the roots.
Plant when the weather is cooler in winter and choose a sunny spot with good soil. Frequent irrigation is crucial during the establishment period and when the fruit is produced. Weed control with organic or plastic mulches is also important to the success of your blackberry patch.
For more information on blackberry cultivars, propagation and growing success please see the University of Florida publication The Blackberry.
Although blackberries are well adapted to North Florida, many different biotic and abiotic factors can impact fruit production. Photo by Molly Jameson.
Diagnosing Abiotic Blackberry Fruit Disorders
Whether it be wild blackberries you’ve foraged or a prized cultured variety you’ve oh-so-carefully sustained, we are now in prime blackberry season, and there are many sweet, tangy delectable fruits to be eaten.
Blackberry bushes are well adapted to the Florida Panhandle and the plants can be found growing all over – along roadways, in ditches, throughout open fields, and also within forests.
Although wild blackberries and domesticated cultivars thrive in our climate, there is a wide range of factors that could affect blackberry fruiting. When diagnosing plant problems, we tend to blame insects and diseases, but there are many abiotic (non-living) factors that could negatively impact blackberry fruit production. If your blackberry drupelets (the small subdivisions that comprise a blackberry fruit) are compromised, you may be experiencing one or more of the following abiotic blackberry disorders.
Although blackberries can self-pollinate, insect pollination is critical for forming the best blackberries. Photo by Johnny N. Dell, Bugwood.org.
Poor Pollination. Blackberries, strangely enough, are not true berries botanically. True berries only have one ovary per flower (such as bananas, watermelons, and avocados!). Each blackberry flower contains over 100 female flower parts, called pistils, that contain ovaries. To form a fully sized blackberry with many drupelets, at least 75% of the ovaries need to be pollinated. While blackberries can self-pollinate, pollinator insects, such as bees, are very important to ensure adequate drupelet formation. When weather conditions are overly cloudy and rainy, bees are less active. If this coincides with blackberry flowering, you may end up with some blackberries that are nearly drupe-less.
White Drupe. If you notice patches of white and brown drupelets on your most sun-exposed canes, you might have white drupe disorder. When humidity drops and temperature heats up, solar radiation contacting your berries is more powerful, as there is less moisture in the air to deflect the intense heat. Berries that are not protected by leaf coverage, and those on trellises oriented for maximum sun exposure, are most vulnerable to white drupe damage.
Sunscald. Often associated with white drupe, sunscald is most common when temperatures are extreme. Daytime highs in the Florida Panhandle in June and July regularly reach 90°F, if not higher. At these times, fruit exposed to the sun can be hotter than the air temperature around them, which essentially cooks the fruit. As I suspect you’d prefer to cook your fruit after harvest in preparation for blackberry pie, orient your trellis so it gets shade relief during the hottest part of the day and harvest often.
Diagnosing a blackberry issue can be challenging, as there can be more than one culprit impacting the fruit. Photo by Molly Jameson.
Red Cell Regression. One of the not-so-well understood abiotic blackberry disorders is red cell regression, or red drupelet disorder. If you’ve ever harvested blackberry fruit and stored them in the refrigerator for later munching, you may think your eyes are deceiving you when you discover your fruit doesn’t appear as ripe as when you picked it. This regression in color is linked to rapid temperature change, but rest assured, it does not affect the sugar content of the fruit. There are a few things you can do if you think this is affecting your berries, such as harvesting in the morning when the berries are still cool, harvesting when the sky is overcast, or shading your berries pre-harvest. You can also try to cool your berries in stages, perhaps moving from the field, to shade, to A/C, and then to the fridge.
Beyond abiotic stresses, blackberries can also suffer from insect, pest, and disease damage, such as from stink bugs, beetles, mites, birds, anthracnose, leaf rust, crown gall, and beyond. For domesticated blueberry bushes, proper cultivar selection, site selection, planting technique, fertilization, irrigation, propagation, and cane training is important and will allow the plants to grow healthy to defend themselves against any abiotic or biotic nuisance that comes their way.
For more information about growing blackberries, check out the EDIS publication, The Blackberry (https://edis.ifas.ufl.edu/hs104).
Homeowners are always looking for methods to manage one of our most difficult pests in the vegetable garden. Learn about the science of how to properly use marigolds to deter nematodes against one our our favorite summer fruits In the Garden with UF IFAS Extension Escambia County.
Spring is in the air, and that means temperatures are warming up and tank-tops, shorts, and flip-flops will soon be your preferred attire. Once those highs are steadily in the 80s and 90s, any outdoor activity will become coupled with a bottle of water and the occasional ice-cold glass of lemonade.
Self-watering containers allow you to continue gardening even if you plan on going on vacation this summer. Photo by Molly Jameson.
If you’re a gardener, you will notice the hot sun doing its best to dehydrate not only you, but your spring vegetable and flower beds too. And although April showers bring May flowers (and Mayflowers bring pilgrims) in many parts of the country, spring is historically one of the driest periods for the Florida Panhandle.
While spring in the Florida Panhandle can be quite dry, it is the relentless heat of summer that really drives up transpiration and evaporation rates. And herein lies the dilemma: the kids are soon to be on summer break, family vacations are on the horizon, and all your favorite summer veggies are on the brink of delivering their bounties.
If you do not have a reliable irrigation system and timer or the fortune of a very generous green-thumbed neighbor, you risk your hard work in the garden succumbing to the heat while you are away. If you find yourself sacrificing a summer garden in place of a vacation, don’t despair. There is a low-cost, homemade solution that can step in while you are away: a self-watering container garden.
Self-watering containers use the process of capillary action, where water molecules are pulled upward from a water reservoir into soil above and then into and through plant roots. The forces of cohesion, in which water molecules stay close together, and adhesion, in which water molecules “stick” to other substances, create this important phenomenon.
A wicking basket uses capillary action to pull water molecules up from the water reservoir and into the soil. Photo by Trevor Hylton.
While store-bought versions can be costly, you can make a self-watering container for less than $10 with just a few materials and tools. There are multiple designs for creating a self-watering container at home. Typically, designs include two five-gallon food-grade plastic buckets to hold the soil and plant; a knife or hole saw to access the water reservoir; a wicking basket or strips of cotton from an old towel, pants, or shirt to generate the capillary movement of water; a drill and drill bit for drainage; and a plastic pipe for easy filling of the water reservoir.
To make your own, view these Extension-produced self-watering container garden resources and follow the step-by-step instructions that work best for you:
Twisted and tangled kiwifruit plants in a North Florida orchard. Photo Credit: Matt Lollar, University of Florida/IFAS Extension – Santa Rosa County
When we think of kiwis, we think of fuzzy, slightly tart, egg-shaped fruits from somewhere in the Southern Hemisphere. However, there is a species (Actinidia chinensis) of kiwi with smooth skin, sweet taste, and golden color.
Commonly available cultivars of this species are ‘AU Golden Dragon’ and ‘AU Golden Sunshine’. Most years, kiwis won’t produce much of a crop in North Florida because they won’t receive enough chill hours, but they might be fun to try for the adventurous gardener.
- Site Selection – Kiwis perform best in well-drained soils with a neutral pH (around 7.0). High winds may cause canes to break and scar fruit, so a windbreak is recommended or they can be planted near a structure.
- Irrigation – Kiwis need a lot of water during the summer. This is partly due the their large leaves that transpire rapidly because of surface area. Newly planted kiwis should be watered deeply at least once a week.
- Fertilization – Fertilize kiwis three times a year (January, April, and June). Do not apply fertilizer after the month of July to reduce the incidence of cold injury in the winter.
- Insects and Diseases – The most common insects of kiwis are mites and scales. To reduce the incidence of disease, plant kiwis at least 15 feet apart and train on a trellis.
- Training – A T-bar trellis, similar to the system used to train grape vines, or a pergola should be used to provide support for the plants. Once the plants are established (2 to 3 years after planting), about a third of the vines should be removed each year.
An illustration of a T-bar trellis system. University of Georgia Extension
Kiwis are wind- and insect-pollinated. Good growing conditions and insect pollination help increase fruit size. Male and female plants are required for good fruit yields. At least one male (pollen producing) plant should be planted for every four female (fruit producing) plants.
Kiwi plants will soon be planted for evaluation at the West Florida Research and Education Center in Jay, FL. Please stay tuned for future data! For more information on growing kiwis in the Southeast, please visit these webpages:
Kiwifruit Production Guide
Bringing Home the Gold – Auburn horticulture alum gets kiwifruit orchard off the ground in Reeltown
Winter is in full swing and home grown produce is probably not the first thing that comes to mind. But it should be! It’s time again to start thinking about spring vegetable gardening. While a number of crops can be started by direct seeding in the soil, success rates are higher when plants are started indoors or in a covered structure. In order to be successful, it’s important that you follow some simple steps.
Seedless watermelons planted in a 128-cell flat. Photo Credit: Gene McAvoy, University of Florida/IFAS Extension – Hendry County
- Transplant Trays/Flats – Trays are made from different materials such as plastic, polystyrene, and compostable materials. Different cell sizes are also available. Generally, smaller cells are used for smaller seeds and larger cells are used for larger seeds. It’s important to think of the life cycle of the crop. For example, lettuce and other leafy greens have much shorter life cycles compared to tomatoes. Because of this, they have smaller root systems at transplant time and may not develop a good rootball in a large cell. Therefore, lettuce would perform better in a smaller cell.
- Media – It’s important that you choose a germination mix instead of a potting mix. Definitely don’t use garden soil! Germination mixes are typically a combination of finely ground peat, perlite, and other soiless substrates.
- Seed – Purchase seed from a reputable source with a germination guarantee. If you save seeds for future gardening, then store them in a cool, dry place. Seed can be stored in the refrigerator. However, do expect the germination rate of stored seeds to diminish over time. Coated seed is recommended for smaller seeds to make seeding easier and more efficient. Seeds should be planted in media at a depth of approximately 3 times the diameter of the seed. Check the seed package for additional planting recommendations. For more germination and storage information please see this publication from the University of Nebraska.
- Fertilizer – Too much fertilizer can result in leggy and possibly burned plants. A 20-10-10 (or similar ratio N-P-K) water-soluble product is generally used in commercial production. Rates are dependent on crop, sunlight, and temperature. The media should be kept moist, but not continually wet.
Well-grown kale transplants ready for field planting. Photo Credit: Gene McAvoy, University of Florida/IFAS Extension – Hendry County
Seeds can take up to 14 days to germinate depending on species and conditions. Most transplants are ready for the garden by 6 to 8 weeks. To improve success rate and accelerate production time, most farmers harden off their transplants before planting. Hardening off is the process of stressing the transplants for about a week. Generally, transplant trays are taken out of the greenhouse (or other transplant area such as a window sill) and set outside. Watering frequency is reduced and fertilization is halted. It’s important that the plants aren’t completely neglected, but just stressed enough to prepare them for the elements. A good place to put the trays is under a tree in partial shade. After this hardening off period, the transplants are ready for your garden. Hopefully these tips will make you a more successful gardener!