by Matt Lollar | Sep 7, 2019
A couple weeks ago, I was on a site visit to check out some issues on Canary Island Date Palms. The account manager on the property requested a site visit because he thought the palms were infested with scale insects. He noticed the issue on a number of the properties he manages and he was concerned it was an epidemic. From a distance, lower fronds were yellowing from the outside in and the tips were necrotic. These are signs of potassium deficiency with possible magnesium deficiency mixed in.
Transitional leaf showing potassium deficiency (tip) and magnesium deficiency (base) symptoms. Photo Credit: T.K. Broschat, University of Florida/IFAS Extension
Nutrient deficiencies are slow to correct in palm trees. It’s much easier to prevent deficiencies from occurring by using a palm fertilizer that has the analysis 8N-2P2O5-12K2O+4Mg with micronutrients. Even if the palms are part of a landscape which includes turf and other plants that require additional nitrogen, it is best to use a palm fertilizer with the analysis previously listed over a radius at least 25 feet out from the palms. However, poor nutrition wasn’t the only problem with these palms.
Upon closer look, the leaflets were speckled with little bumps. Each bump had a little white tail. These are the fruiting structures of graphiola leaf spot also known as false smut.
Graphiola leaf spot (false smut) on a Canary Island Date Palm. Photo Credit: Matt Lollar, University of Florida/IFAS Extension – Santa Rosa County
Graphiola leaf spot is a fungal leaf disease caused by Graphiola phoenicis. Canary Island Date Palms are especially susceptible to this disease. Graphiola leaf spot is primarily an aesthetic issue and doesn’t cause much harm to the palms infected. In fact, the nutrient deficiencies observed in these palms are much more detrimental to their health.
Graphiola leaf spot affects the lower fronds first. If the diseased, lower fronds are not showing signs of nutrient deficiencies then they can be pruned off and removed from the site. All naturally fallen fronds should be removed from the site to reduce the likelihood of fungal spores being splashed onto the healthy, living fronds. A fungicide containing copper can be applied to help prevent the spread of the disease, but it will not cure the infected fronds. Palms can be a beautiful addition to the landscape and most diseases and abiotic disorders can be managed and prevented with proper pruning, correct fertilizer rates, and precise irrigation.
by Julie McConnell | Aug 22, 2019
Until plans were underway for our UF/IFAS Demonstration Butterfly Garden, I had never heard of Cutleaf Coneflower, Rudbeckia lacineata. Master Gardener Volunteer Jody Wood-Putnam included this gem in her garden design and introduced me and many of our visitors to a new garden favorite.
Although in the same genus as your common Black-eyed Susan’s (Rudbeckia fulgida or R. hirta) this perennial has very distinct differences. Rather than the low growing, hairy, oblong leaves of Black-eyed Susan, Cutleaf Coneflower has smooth pinnately lobed leaves with serrated edges. The leaves are still clump forming but form an almost bush-like shape. By mid to late summer, tall flower spikes emerge and are covered in bright yellow flowers bringing the overall height of the plant over 5 feet tall!
Cutleaf Coneflower is native to North America with several variations adapted to different regions including the Southeast and Florida. This perennial performs well in full sun to part shade and needs a lot of space. Mature plants can reach 3’ wide by 10’ tall and may require staking. The plant can spread through underground runners, so be sure to give it lots of space. In North Florida leaves may be evergreen if winter is mild. Cutleaf Coneflower is a good wildlife attractant providing nectar and pollen for many insects and if you leave the flowers on to mature the seed the is eaten by songbirds, including goldfinch.
To see this plant in person, stop by the UF/IFAS Demonstration Garden at 2728 E. 14th Street, Panama City, FL. If during normal business hours, check in for available seeds from our Pollinator Garden. 850-784-6105
by Beth Bolles | Aug 7, 2019
We are always on the lookout for an attractive plant for our landscape. At the nursery, some plants have a more difficult time gaining our attention. They may not be as showy, possessing neither colorful flowers nor bold foliage. In these cases, we could be missing out on low maintenance plant that offers its own form of beauty in the right landscape spot.
One plant that I love is the Japanese plum yew (Cephalotaxus harringtonia), especially the spreading form ‘Prostrata’. In the nursery container, this plant is nothing special but once established in the landscape it performs well. The conifer type leaves are an attractive dark green and the ‘Prostrata’ selection is low growing to about 2 to 3 feet. An advantage too is that growth is slow so it won’t take over or require routine pruning.
Japanese plum yews grow best in partial shade and once established will be fine with rainfall. For a shadier side of the home, the spreading plum yew has a place as an evergreen foundation plant too.
Japanese plum yew in a shaded garden. Photo by Beth Bolles, UF IFAS Extension Escambia County
If the ‘Prostrata’ selection is too low growing for you, consider the ‘Fastigiata’ cultivar that will grow upright to about 8 feet with a 5 foot spread.
A year old planting of upright Japanese plum yew in filtered light. Photo by Beth Bolles, UF IFAS Extension Escambia County
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 Carrie Stevenson | Apr 16, 2019
Historic live oaks provide shade and wildlife habitat at the Escambia Extension walking trail. Photo credit: Carrie Stevenson, UF / IFAS Extension
A recent study of 3-5 year olds found that the average pre-reading American child could identify hundreds of marketing brand logos (McDonald’s, Disney, even Toyota). Most researchers would be mightily challenged to find even a middle school student who can identify more than a couple of trees growing in their own backyard. The fields and forests many of us grew up in are steadily converting to look-alike suburban areas, so this lack of local natural knowledge is commonplace. As the quote by Senegalese forester Baba Dioum goes, “In the end, we will conserve only what we love; we will love only what we understand and we will understand only what we are taught.” If kids and adults do not appreciate and understand the natural world around them, we are unlikely to preserve these priceless wonders.
To do our part towards this aim of educating others, we at Escambia Extension received a grant from International Paper to plant 30 trees around our office’s walking track. Every tree has a clearly marked identification tag listing its common and botanical name.
A newly planted sassafras tree on the Extension walking trail. Photo credit: Carrie Stevenson, UF / IFAS Extension
Initially we just planned to add more shade trees to the sunny side of the track, but after a discussion with local foresters, we realized this effort could be an ideal teaching tool. The local middle and high school Future Farmers of America (FFA) chapters participate in a tree identification contest, and are tasked with knowing 50 native tree species. While 10 of them were tropical species that do not perform well in north Florida, we have the other 40 planted here on the property. Students and any interested citizen interested in learning these native species can walk along our track, getting exercise and taking in the natural world around them.
A spring walking event will kick off the official opening of the tree identification trail, so join us April 26 to learn more about healthy living and the value of trees. Or, join us for an Extension Open House on April 27 to explore the demonstration gardens, purchase vegetable plants, or learn more about Extension’s wide array of community services.
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.
