by Daniel J. Leonard | May 27, 2019
Talk to nearly any Panhandle gardener and one of the first things brought up in conversation is the difficulty growing large, beefsteak/slicing tomatoes (Solanum lycopersicum) in their home garden. Large tomatoes are indeed among the more challenging garden vegetables in North Florida, affected by myriad pests, pathogens and abiotic issues. However, giving up growing this garden favorite is unwarranted as success can be had by following a couple of often overlooked, simple steps to ward off potential problems.
Choose Resistant Cultivars – One of the major recent gardening trends is the rise of heirloom veggies, particularly heirloom tomatoes. While many of these varieties certainly are interesting and often possess superior flavor/texture, heirlooms are, as a group, extraordinarily susceptible to disease in our climate. Fortunately for gardeners, there are a number of excellent varieties available with large resistance profiles to many common diseases and a similar taste profile to heirloom favorites! ‘Big Beef’ (pictured), ‘Better Boy’, ‘Celebrity’, and ‘Skyway’ are just a few of the many great cultivars with extensive disease resistance available as transplants at garden centers or as seed from quality online seed vendors.
Tomato ‘Big Beef’ in 15 gallon decorative container
Start Early – Once, you’ve selected the proper cultivar, the next key is to get them in the ground early! I’m convinced one of the primary reasons folks fail with tomatoes is waiting for “traditional” garden planting dates. For instance, an old tradition in the South is to plant your garden on Good Friday before Easter. However, according to Johnny’s Selected Seeds Southeast Sales Representative Blake Thaxton, tomatoes should be germinated and growing in the garden no later than March 15. Mr. Thaxton notes two primary reasons for this, the most important being pest/disease avoidance. Beefsteak tomato varieties take around 70 days from planting to harvest, so a March 15th planting date yields ripe tomatoes around the third or fourth week of May, when pest/disease pressure is still manageable. Pests and disease occurrence becomes exponentially worse in the Panhandle as May trickles into June and July, therefore it is critical that your fruit begin ripening prior to this onslaught. An important second motivation to plant early is that tomatoes stop setting fruit when nighttime temperatures rise above 75°F. At these temperatures, tomato pollen is rendered sterile and though the plant will continue flowering, no fruit will be set.
Mulch – Another overlooked best management practice in backyard veggie gardening is mulching! Those of us who tend flower beds already know many benefits of mulch like soil temperature moderation, weed prevention, and moisture conservation. But for tomato growers, mulch has another benefit – disease prevention! Several serious diseases that affect tomato are soil-borne pathogens (i.e. Early Blight, Late Blight, Bacterial Spot, etc.). These pathogens find their way onto plants either indirectly via water splashing from soil onto leaves or direct contact from leaves and fruit resting on the soil. To prevent these pathogens from infecting plant tissue, apply an organic mulch (preferably wheat straw or tree leaves) under and around plants. This simple step goes a long way toward season-long, yield-saving disease prevention.
Consistent Watering – Everyone knows plants need water but what you might not know is that irrigation consistency makes a huge difference in plant health, particularly tomatoes. Consistent watering is key in helping ward off one of the most frustrating tomato maladies, blossom end rot (BER) – you know, the one where the bottom end of your perfectly good tomato fruit turns to a brownish mush! Though BER is caused by calcium deficiency, the condition is commonly induced by creation of distinct wet and dry periods from non-regular watering, interfering with calcium uptake and availability to the plant. So, while you may have adequate soil calcium, if you don’t water correctly, the condition will happen anyway! It’s also good to keep in mind that mature tomato plants use large quantities of water daily, so during the heat of summer, plants in containers may need to be watered multiple times daily to maintain consistently moist soil. Think about it, you don’t drink 8 glasses of water when you wake up and then never drink again throughout a hot day. A tomato is no different. Allowing your plants to wilt down before providing additional water ruins productivity and can induce BER.
Tomato ‘Big Beef’ demonstrating pruning for soil clearance and airflow.
Pruning – I get it. Once you’ve nursed your baby tomato from a wee transplant or seed into a rapidly growing and flowering plant, it seems counter-intuitive to break out the pruners, but to keep your tomato plant as healthy as possible for as long as possible, that is what you must do! Pruning tomatoes should accomplish two things. First, remove the bottom layer of foliage from the plant base, so that water will not readily splash onto the lowest remaining leaves. (I tend to remove all leaves up to the second set of flowers 8-12” from the soil’s surface.) As with mulching, this prevents bacterial and fungal pathogens from spreading easily from the soil surface onto your plant. Second, tomato plants, especially the vigorous indeterminate varieties, often grow more foliage than is necessary for fruit production. This excess foliage can prevent airflow and trap moisture in the canopy of the plant, promoting disease. To open up the canopy and allow for more airflow, I prune off leaves that grow from the primary stems inward to the center of the plant. The idea is to keep the inside of the plant open while allowing enough leaves to power photosynthesis and shade the developing fruit below.
Tomatoes are notoriously hard to grow, but by following a few easy preventative practices, gardeners can greatly increase their chances of realizing harvestable fruit come summer. Please keep in mind that this is not an exhaustive list that will ensure disease-free plants over the entire growing season (you should also get a soil test to make sure your pH and soil fertility are correct and ideally you’d never work in your tomatoes when they are wet, etc., but this is a good place to start!). However, a little bit of planning and prevention early in the season can make growing tomatoes a lot less frustrating! As always, if you have questions regarding tomatoes or any other horticultural topic, please contact your local UF/IFAS Extension Office. Happy gardening!
by Daniel J. Leonard | May 20, 2019
Spring is a wonderful time of year. After months of dreariness and bare branches, bright, succulent green leaves and flowers of every kind and color have emerged. So too, have emerged gardeners and outdoor enthusiasts ready to tackle all their home and landscape improvement projects planned over the winter. However, this is also the time, when folks first start paying attention to their plants again, that strange, seemingly inexpiable plant problems crop up!
All plant problems can be divided into two categories: biotic problems, or issues caused by a living organism (think insects, fungus, and bacteria), and abiotic problems, issues that arise from things other than biotic pests. It’s the first category that people generally turn to when something goes wrong in their landscape or garden. It’s convenient to blame problems on pests and it’s very satisfying to go to the local home improvement store, buy a bottle of something and spray the problem into submission. But, in many of my consultations with clientele each spring, I find myself having to step back, consider holistically the circumstances causing the issue to arise, scout for pests and diseases, and if I find no evidence of either, encouraging the person to consider the possibility the problem is abiotic and to adopt patience and allow the problem to correct itself. Of course, this is never what anyone wants to hear. We always want a solvable problem with a simple cause and solution. But life isn’t always that easy and sometimes we must accept that we (nor a pest/disease) did anything wrong to cause the issue and, in some cases, that we ourselves actually caused the problem to happen in the first place! To illustrate, let’s consider two case studies from site visits I’ve had this spring.
Cold damage on Boxwood hedge
Three weeks ago, I got a call from a very concerned client. She had gotten her March issue of a popular outdoor magazine in the mail, in which was a feature on an emerging pathogen, Boxwood Blight, a nasty fungus decimating Boxwood populations in states north of us. She had also noticed the Boxwoods in front of her house had recently developed browning of their new spring shoots across most the hedgerow. Having read the article and matching the symptoms she’d noticed to the ones described in the magazine article, she was convinced her shrub was infected with blight and wanted to know if there was a cure. Agreeing that the symptoms sounded similar and wanting to rule out an infection of an extremely serious pathogen, I decided to go take a look. Upon inspection, it was obvious that Boxwood Blight wasn’t to blame. Damage from disease generally isn’t quite as uniform as what I saw. The new growth on top of the hedge was indeed brown but only where the eaves of the house and a nearby tree didn’t provide overhead cover and, to boot, the sides of the hedge were a very normal bright green. Having gone through a recent cold snap that brought several mornings of heavy frost and knowing that the weeks before that the weather had been unseasonably warm, causing many plants to begin growing prematurely, all signs pointed toward an abiotic problem, cold/frost damage that would clear up as soon as the plant put on another flush of growth. The client was delighted to hear she didn’t have a hedge killing problem that would require either adopting a monthly fungicide regime or replacing the hedge with a different species.
Damage to ‘Sunshine’ Ligustrum from pressure washing siding with bleach.
The very next week, another client asked if I would come by her house and take a look at a hedge of ‘Sunshine’ Ligustrum that lines her driveway, whose leaves had “bleached” out, turning from their normal chartreuse to a bronzy white color. This time, having seen similar issues with this particular plant that almost always involved an infestation of Spider or Broad Mites, I figured this was a cut and dry case that would end with a call to her pest control company to come spray the offending bugs. However, though the leaf damage looked similar, I was not able to locate any existing pests or find evidence any had been around recently, rather it appeared the leaves had been exposed to something that “bleached” and burned them. Puzzled, I began asking questions. What kind of maintenance occurs on the plants? Have you fertilized or applied any chemicals recently? Nothing. Then, near the end of our conversation, the client mentioned that her neighbor had pressure washed their house on a windy day and that she was irritated because some of the soap solution had gotten on her car. Bingo. Leaf burn from pressure washing solution chemicals. This time I was guilty of assuming the worst from a pest when the problem quite literally blew in on the wind from next door. Again, the client was relieved to know the plant would recover as soon as a new flush of growth emerged and hid the burned older leaves!
This spring, I’d encourage you to learn from the above situations and the next time you notice an issue on plants in your yard, before you reach for the pesticides, take a step back and think about what the damage looks like, thoroughly inspect the plants for possible insects or disease, and if you don’t find any, consider the possibility that the problem was abiotic in nature! And remember, if you need any assistance with identification of a landscape problem and want research-based recommendations on how to manage the problem, contact your local UF/IFAS Extension office.
by Daniel J. Leonard | Apr 8, 2019
Carrots growing in a large container.
After tending a home vegetable garden for any length of time in the Panhandle, you begin to learn some things. Tomatoes are awfully hard to grow. Raised beds drastically lower the difficulty of gardening in general. You should never plant mint in a permanent veggie garden. Swiss Chard has to be started early because it grows as molasses creeps. Of all of these anecdotal maxims I’ve discovered, the one with the most flavor return on my gardening investment is that carrots should always be a part of your cool season garden. A fresh carrot out of the garden is hard to beat. The difference between a grocery store carrot and one fresh out of your own garden is astonishing and will change your culinary life. Though carrot season in Florida is just ending (my final batch was harvested yesterday), it’s the perfect time to learn about growing carrots here and plan to get some in the ground this fall!
There are a number of reasons to grow and eat carrots. They’re obviously very healthy, though I dispute the whole eat carrots and you’ll have great eyesight thing – apparently I acquired the taste for them too late to help. They go well in more dishes than they don’t. However, the real two reasons you should supplement your grocery store carrot purchases with home grown harvests are that they’re so easy to grow and that there are so many more options than the standard long, thin orange varieties adorning the produce aisle shelves.
‘Bolero’ Carrots
Though carrots are remarkable easy to grow, they do ask a couple of things of gardeners. They are a cool season vegetable and are generally planted from seed beginning in late August through early September in the Panhandle, though successive plantings can continue through at least February if you want to extend your harvest. Also, like many other root vegetables, carrots don’t transplant well so direct seeding in the garden is a must. But before you even consider seeding, care must be taken to make sure the soil bed you’ll be seeding in has been properly prepared. One of the few ways to fail growing carrots is to not start with a loose soil free from any potential obstructions. If the development of the carrot root is disturbed by anything during the germination and growing process (this includes manure aggregates or other clumpy soil, sticks, rocks or even a hard layer of soil hiding under your loose compost), the end product will be deformed. To prevent this, thoroughly till your raised bed soil to at least 12” and break up any larger soil particles that are left with your hands. If you don’t get your soil bed perfect though, fear not, deformed carrots are definitely edible, they just won’t look like they’re supposed to and are more difficult to clean and process!
Deformed carrots due to clumpy compost!
Once you’re ready to plant, I’ve found it easier on poor eyes and fumbling fingers like mine to sprinkle the tiny carrot seeds in shallowly furrowed rows 10”-12” apart and thin the seedlings later, rather than trying to individually space seeds the recommended 1”-3” apart. Finally, these colorful little veggies love water and require good fertility. To ensure good expansion of the edible root, maintain consistent moisture and fertilize at planting with a good slow release fertilizer. Additional fertilizer applications may be required later in the growing season as most carrots take around ten weeks to gain maturity.
‘Sugarsnax’ (orange) and ‘Malbec’ (red) carrots
In this age of online catalogs, farmer’s markets, and demanding consumers who crave interesting food, the selection of carrot varieties available for gardeners to grow has never been better. Among the hundreds of individual cultivar options are several broad types of carrots you’ll need to choose from. You’re probably familiar with the Imperator types. These are the extra-long, durable carrots most often find in stores. If you have a deep raised bed or other large container, Imperator varieties can be extremely rewarding! I grew the Imperator-type ‘Sugarsnax’ this year and highly recommend it for ease of growing, size and flavor. Next up are the Nantes types. These carrots are medium length and cylindrically shaped. Sometimes called “storage” carrots, these types tend to store well for long periods of time after harvest and retain their flavor well. I’ve tried a few over the last several years and can recommend ‘Bolero’ and ‘Napoli’ with confidence. There is even a carrot type for those of you with shallow raised beds (8” or less) that can’t accommodate the previously listed types! Chantenay type carrots are excellent performers in these situations as they are generally a bit shorter and possess a conical shape with roots wider at the top and tapering to the tip, making a deep soil bed a bit less critical. Finally, there are even some excellent cultivars of carrots in colors other than orange! That’s right, you can grow white, purple, yellow, and even red carrots! I’ve done very well with ‘Purple Haze’ (purple with orange interior), ‘White Satin’ (creamy white color), and ‘Malbec’ (deep, rich red) and highly recommend all three. Keep in mind that the red and purple carrots tend to lose their color when cooked, so the greatest effect is seen when eaten fresh. All of these cultivars can be found at nearly any of the numerous online and catalog seed retainers such as Johnny’s Selected Seeds, Baker Creek Heirloom Seeds, Burpee, and others.
As you can see, carrots are an easy to grow, extremely rewarding vegetable for the home gardener; give some a try in your raised beds next fall! And as always, if you have any questions about growing carrots or any other gardening related question, contact your local UF/IFAS Extension office!
by Daniel J. Leonard | Jan 18, 2019
Many Americans have a remarkably unrefined taste in salads; my brother has long counted himself in this group. Dice up some crunchy Iceberg type lettuce, splash on a dollop of ranch dressing, maybe chop a leaf of romaine up if you’re feeling frisky and call it a salad, this is the way we’ve been trained to eat. I’m here, a voice in the supermarket produce aisle wilderness calling, to tell you it’s time to open up your palate, look beyond lettuce, live a little, and add some spice to your life and salad bowl with three of my favorite easy to grow leafy greens: Mizuna, Frilly Mustard, and Italian Dandelion.
Mature Mizuna plants in the author’s container garden.
Before we get into species specifics, let’s cover a couple of reasons you should grow them at home! Growing your own flavor-packed greens has many benefits. First, leaves from these plants can be difficult to find anywhere but specialty health food stores or high-end supermarkets. Growing your own ensures a consistent supply, especially if one utilizes the “cut and come again” harvesting method (just remove the leaves and stems you need that day, leave the crown intact and allow the plant to regrow for next week’s harvest). Second, you do not have to worry about the too common food safety recalls and other health scares involving “leafies”. If you follow standard safety practices (clean irrigation water, wash picked leaves and store properly, etc.), you’ll be eating scrumptious salads when everyone else is begrudgingly trashing entire bags of recalled store-bought greens. Finally, each of these species double as gorgeous accent plants in
‘Scarlet Frills’ Mustard in the author’s container garden.
raised beds or containers. I love plants that do heavy lifting as both eye-catching ornamentals and delicious edibles!
Mizuna is a little known member of the mustard family that is quickly becoming one of my favorite leafy greens! It faces no major pest or disease problems in the garden and it is extremely tolerant of the cold weather Floridians periodically face through the winter, laughing off frost. Mizuna possesses lovely, deeply cut, pale green, fringy leaves complete with crispy white stems, all of which are edible – no need to separate stems when processing to eat! This lovely little Asian green has a mild peppery taste (think a toned-down Arugula) and adds perfect flavor and texture to any salad!
Many Southerners are well acquainted with traditional Mustard greens and their preparation (more than a little bacon and salt) but may not be aware of newer Mustard cultivars that give the species a bit of refinement and make it a salad celebrity! This winter, I’m growing a cultivar of Mustard called ‘Scarlet Frills’ (aptly named with finely serrated burgundy-red leaves) and really enjoy its peppery horseradish taste as a foil to the mildly sweet taste of traditional salad greens like lettuce and spinach. Mustards are extremely cold tolerant and slow to bolt, making it a mainstay in the salad garden all winter long; you really get your money’s worth from a few Mustard plants! However, even if this leafy green wasn’t delicious, it would be worth growing. The “fancier” Mustard cultivars are highly ornamental and deserve a spot in any cool season container garden.
‘Italiko Red’ Italian Dandelion in the author’s container garden.
Finally, the one that turns up the most noses when I mention growing and eating it, Italian Dandelion (Cichorium intybus)! I’m not advocating foraging in your turfgrass to find dinner, in fact, Italian Dandelion is not a true dandelion (it’s actually a chicory). However, it does share a number of features with its weedy cousin, including leaves that are similar in appearance and a vigorous taproot. That’s where the comparisons stop though, as Italian dandelion is a superior garden plant, more upright growing, much larger, and deeper green (some varieties including the one I grow ‘Italiko Red’ have red veined leaves) than its wild cousin. Unlike Mizuna and some of the milder mustards, Italian Dandelion is a bit of an acquired taste. It imparts a strong bitter flavor that may be cut with milder greens in a salad or cooked down to reduce bitterness. Either way you try it, put Italian Dandelion on your cool season garden next year!
Mizuna, Frilly Mustard, and Italian Dandelion all require similar growing conditions. In Florida, leafy greens are cool season vegetables, growing through the fall, winter and spring months. Seeds should be sown in late September and can be stagger-sown (plantings every couple of weeks) to ensure a steady supply through spring. As a rule, they prefer rich, well-drained soil high in organic matter. These soil conditions are achievable with either quality commercial potting mixes or homemade concoctions of compost and pine bark. The beds or containers you fill with the aforementioned soil should be sited near a good water source (plants that aren’t convenient to water get neglected, trust me) in an area that gets 6-8 hours of full sunlight. I like to topdress at planting (if using transplants) or after germination (if using seed) with a good general purpose, slow-release fertilizer, many formulations and brands that work are widely available for purchase. Finally, be sure to purchase seed from a quality source. Online purveyors Johnny’s Selected Seeds, Baker Creek Heirloom Seeds, and Sow True Seeds are good places to start, though the options are nearly endless!
Next year, when planning your cool season garden, remember to add a little spice with these three leafy greens, Mizuna, Frilly Mustard, and Italian Dandelion! For more information about cool season gardening and other topics, consult your local UF/IFAS Extension Office.
by Daniel J. Leonard | Nov 21, 2018
After a devastating windstorm, as we just experienced in the Panhandle with Hurricane Michael, people have a tendency to become unenamored with landscape trees. It is easy to see why when homes are halved by massive, broken pine trees; pecan trunks have split and splayed, covering entire lawns; wide-spreading elms were entirely uprooted, leaving a crater in the yard. However, in these times, I would caution you not to rush to judgement, cut and remove all trees from your landscape. On the contrary, I’d encourage you, once the cleanup is over and damaged trees rehabilitated or disposed of, to get out and replant your landscape with quality, wind-resistant trees.
First, it’s helpful to take a step back and remember why we plant and enjoy trees and the important role they play in our lives. Beyond the commercial aspect of farmed timber, there are many reasons to be judicious with the chainsaw in the landscape and to plant anew where seemingly sturdy trees once stood. For example, trees provide enormous service to homes and landscapes, from massive cooling effects to aesthetic appeal. Take this thermal satellite image of Hurricane Michael’s path that simultaneously shows the devastation of a major hurricane and the role trees play in the environment.
Lightly shaded area showing higher ground temperatures from loss of vegetation.
In the lighter colored areas where the wind was strongest and catastrophic tree damage occurred, the ground temperatures are much higher than the unaffected areas. Lack of plant life is entirely to blame. Plants, especially trees, provide enormous shading effects on the ground that moderate ground temperatures and the process of transpiration releases water vapor, cooling the ambient air. Trees also lend natural beauty to neighborhood settings. There is a reason people termed the hardest hit areas by Michael “hellscapes”, “warzones”, etc. Those descriptions imply a lack of vegetation due to harsh conditions. In this respect, trees soften the landscape with their foliage colors and textures, create architecture with their height and shape, and screen people from noise, unpleasant sights and harsh heat.
Though all trees give us the benefits outlined above, research conducted by the University of Florida over a span of ten major hurricanes, from Andrew to Katrina, shows that some trees are far more resistant to wind than others and fare much better in hurricanes. In North Florida, the trees that most consistently survived hurricanes with the least amount of structural damage were Live Oaks, Cypresses, Crape Myrtle, American Holly, Southern Magnolia, Red Maple, Black Gum, Sycamore, Cabbage Palm and a smattering of small landscape trees like Dogwood, Fringe Tree, Persimmons, and Vitex. If one thinks about these trees’ growth habits, broad resistance to disease/decay, and native range, that they are storm survivors comes as no surprise. Consider Live Oak. This species originated along the coastal plain of the Southeastern United States and have endured hurricanes here for several millennia. Possessing unusually strong wood, they have also developed the ability to shed the majority of their leaves at the onset of storms. This defense mechanism leaves a bare appearance in the aftermath but allows the tree to mostly avoid the “umbrella” effect other wide crowned trees experience during storms and retain the ability to bounce back quickly. Consider another resistant species, Bald Cypress. In addition to having a strong, straight trunk and dense root system, the leaves of Bald Cypress are fine and featherlike. This leaf structure prevents wind from catching in the crown. Each of the other listed species possess similar unique features that allow them to survive hurricanes and recover much more quickly than other, less adapted species.
Laurel Oak split from weak branching structure.
However, many widely grown native trees and exotic species simply do not hold up well in tropical cyclones and other wind events. Pine species, despite being native to the Coastal South, are very susceptible to storm damage. The combination of high winds and beating rains loosens the soil around roots, adds tremendous water weight to the crown high off the ground, and puts the long, slender trunks under immense pressure. That combination proves deadly during a major hurricane as trees either uproot or break at weak points along the trunk. In addition to pines, other widely grown native species (such as Pecan, Laurel Oak and Water Oak) and exotic species (such as Chinese Elm) perform poorly in storms. Just as the trees that survive storms well possess similar features, so do these poor performers. We’ve already mentioned why pines and hurricanes don’t mix well. Pecan, Laurel Oak, and Water Oak tend to have weak branch angles and break up structurally in wind events. The broad spreading, heavy canopy of trees like Chinese Elm cause them to uproot and topple over. It would be advisable when replanting the landscape, to steer clear of these species or at least site them a good distance from important structures.
This piece is not a warning to condemn planting trees in the landscape; rather it is a template to guide you when selecting trees to replant. Many of our deepest memories involve trees, whether you first climbed one in your grandparent’s yard, fished under one around a farm pond, or carved your initials into one in the forest. Don’t become frustrated after a once in a lifetime storm and refuse to replant your landscape or your forest and deprive your children of those experiences. As sage investor Warren Buffett once wisely said, “Someone is sitting in the shade today because someone planted a tree a long time ago.”
For these and other recommendations about how to “hurricane-proof” your landscape, contact your local UF/IFAS Extension Office. Plant a tree today.
