Pomegranates in the Panhandle

Pomegranates in the Panhandle

Last week at the Panhandle Fruit and Vegetable Conference, Dr. Ali Sarkhosh presented on growing pomegranate in Florida.  The pomegranate (Punica granatum) is native to central Asia.  The fruit made its way to North America in the 16th century.  Given their origin, it makes sense that fruit quality is best in regions with cool winters and hot, dry summers (Mediterranean climate).  In the United States, the majority of pomegranates are grown in California.  However, the University of Florida, with the help of Dr. Sarkhosh, is conducting research trials to find out which varieties do best in our state.

In the wild, pomegranate plants are dense, bushy shrubs growing between 6-12 feet tall with thorny branches.  In the garden, they can be trained as small single trunk trees from 12-20 feet tall or as slightly shorter multi-trunk (3 to 5 trunks) trees.  Pomegranate plants have beautiful flowers and can be utilized as ornamentals that also bear fruit.  In fact, there are a number of varieties on the market for their aesthetics alone.  Pomegranate leaves are glossy, dark green, and small.  Blooms range from orange to red (about 2 inches in diameter) with crinkled petals and lots of stamens.  The fruit can be yellow, deep red, or any color in between depending on variety.  The fruit are round with a diameter from 2 to 5 inches.

 Fruit, aril, and juice characteristics of four pomegranate cultivars grown in Florida; fruit harvested in August 2018. a) ‘Vkusnyi’, b) ‘Crab’, c) ‘Mack Glass’, d) ‘Ever Sweet’.

Fruit, aril, and juice characteristics of four pomegranate cultivars grown in Florida; fruit harvested in August 2018. a) ‘Vkusnyi’, b) ‘Crab’, c) ‘Mack Glass’, d) ‘Ever Sweet’. Photo Credit: Ali Sarkhosh, University of Florida/IFAS

A common commercial variety, ‘Wonderful’, is widely grown in California but does not perform well in Florida’s hot and humid climate.  Cultivars that have performed well in Florida include: ‘Vkusnyi’; ‘Crab’; ‘Mack Glass’; and ‘Ever Sweet’.  Pomegranates are adapted to many soil types from sands to clays, however yields are lower on sandy soils and fruit color is poor on clay soils.  They produce best on well-drained soils with a pH range from 5.5 to 7.0.  The plants should be irrigated every 7 to 10 days if a significant rain event doesn’t occur.  Flavor and fruit quality are increased when irrigation is gradually reduced during fruit maturation.  Pomegranates are tolerant of some flooding, but sudden changes to irrigation amounts or timing may cause fruit to split.

Two pomegranate training systems: single trunk on the left and multi-trunk on the right.

Two pomegranate training systems: single trunk on the left and multi-trunk on the right. Photo Credit: Ali Sarkhosh, University of Florida/IFAS

Pomegranates establish best when planted in late winter or early spring (February – March).  If you plan to grow them as a hedge (shrub form), space plants 6 to 9 feet apart to allow for suckers to fill the void between plants.  If you plan to plant a single tree or a few trees then space the plants at least 15 feet apart.  If a tree form is desired, then suckers will need to be removed frequently.  Some fruit will need to be thinned each year to reduce the chances of branches breaking from heavy fruit weight.

Pomegranate fruit affected by anthracnose.

Anthracnose caused by Colletotrichum sp. to pomegranate fruit. Photo Credit: Gary Vallad, University of Florida/IFAS

Anthracnose is the most common disease of pomegranates.  Symptoms include small, circular, reddish-brown spots (0.25 inch diameter) on leaves, stems, flowers, and fruit.  Copper fungicide applications can greatly reduce disease damage.  Common insects include scales and mites.  Sulfur dust can be used for mite control and horticultural oil can be used to control scales.

July Is Smart Irrigation Month

July Is Smart Irrigation Month

The Irrigation Association (IA) kicks off the official start of this year’s campaign on Tuesday, July 9, 2019. The initiative promotes the social, economic and environmental benefits of efficient irrigation technologies, products and services in landscape, turf and agricultural irrigation.

Irrigation (agricultural and turf/landscape) accounts for 65-70% of total freshwater use in the United States. According to the Environmental Protection Agency’s (EPA) WaterSense program, the average American family household uses more than 300 gallons of water per day; roughly 30% of this occurs outdoors. Efficient landscape irrigation systems and practices dramatically reduce water being lost or wasted.

The starting point for improving the efficiency of a home landscape sprinkler system is to calibrate each zone (http://ufdc.ufl.edu/IR00003389/00001) and make adjustments and repairs. That includes the rain shut-off device.

Florida is one of the few states with a rain sensor law. The most recent version of the statute (2010) states the following: “Any person who operates an automatic landscape irrigation system shall properly install, maintain, and operate technology that inhibits or interrupts operation of the system during periods of sufficient moisture.” (Florida Statute 373.62). Regardless of the water source or age of the system, all in-ground irrigation systems must be connected to a functioning rain sensor of some kind.

Rain collecting device with expanding cork disks inside.

Expanding disk Rain Sensor

Expanded disk devices are the most popular rain sensor due to their low cost, ease of installation, and low maintenance. Traditionally, they are wired into the controller, but a wireless version allows for quicker installation and mounting up to 300 feet from the controller. These “mini-click” sensors contain disks made of cork that absorb rainfall and expand, triggering a pressure switch. The disk cover is rotated to adjust for the predetermined amount of rainfall required to trigger the switch. It should be set on ½ – ¾ inch, depending on soil type and rooting depth of irrigated plants. The switch continues to interrupt the scheduled controller as long as the disks are swollen. When the rain stops, the disks begin to dry out. Once they have contracted, the switch closes and the regularly scheduled irrigation cycle begins where it left off before the interruption. These small cork disks wear out in Florida’s heat and need to be replaced. By checking and repairing the sensor parts, the sprinkler system will operate much more efficiently. We have all seen irrigation systems running in pouring rain.  Keep yours maintained to avoid this needless waste of water.

So, join the kids this summer. Go outside and play in the water. Turn on the sprinkler system and check it out. July is Smart Irrigation Month. Let’s see how efficient you can make your system and reduce the water waste in Florida.

Beat the Heat With a Self-Watering Container Garden

Beat the Heat With a Self-Watering Container Garden

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.

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 into the soil. Photo by Trevor Hylton.

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:

Heating up with Hardy Hibiscus

Each time I travel to central and south Florida and observe the wonderfully flamboyant tropical flora, I am reminded of the unique and frustrating climatic characteristics of Northwest Florida.  Our weather is tropical enough through the summer to sustain virtually everything our friends to the south grow, but winters north of the Big Bend are just cold enough to prevent long-term success with most tropical species.  However, the genus that is maybe most synonymous with tropical color, the Hibiscus (it even has its own texting emoji!), contains several species that are hardy through our winters.  The best landscape plant of these hardy Hibiscus species is creatively (sarcasm) called Hardy Hibiscus or Giant Rose Mallow (Hibiscus moscheutos) and is an absolute star in the Panhandle, bringing the beauty of the tropics to your yard!

Hibiscus ‘Starry Starry Night’ – Photo courtesy Daniel Leonard

Rose Mallow is a native perennial species that occurs in sunny wetlands across the eastern U.S.  This species can grow 7-8’ in height in its natural, unimproved state and possesses the largest flowers of any hardy perennial, some varieties easily eclipse 12” in diameter.  Rose Mallows bloom through the heat of our long summers and return reliably each winter unfazed by frost.  The flowers also happen to be a favorite of butterflies and hummingbirds and bring beneficial wildlife to the landscape.  These characteristics and the trend towards the use of pollinator friendly, low-maintenance native perennials in landscapes quickly made Rose Mallow a jewel for plant breeders and now virtually all major horticultural brands have a line of Hardy Hibiscus available at garden centers, in varying sizes, flower color and leaf color/form.  Recent breeding efforts have focused on introducing plants with enormous, richly colored flowers held on compact plants with attractive foliage.  The results have yielded two series and three individual cultivars that I consider superior selections and are more than worthy of inclusion in your garden:

  • Summerific® Series by Proven Winners. This series is comprised of four robust (up to 5’ in height) cultivars, ‘Cherry Cheesecake’ (bicolor magenta and white flowers), ‘Berry Awesome’ (purplish lavender flowers), ‘Cranberry Crush’ (a red you really have to see to believe), and ‘Perfect Storm’ (notable for its deep purple foliage).
  • Luna Series by Monrovia. This series is notable for its ultra-compact (3’ in height or less) size and characteristically large flowers.  It is also composed of four cultivars, ‘Luna Red’ (deep red), ‘Luna Blush’ (white, fading to pink near flower margins), ‘Luna Pink Swirl’ (pictured and my favorite, bicolor swirly flowers), and ‘Luna White’ (white with a red center).

    Hibiscus ‘Luna Pink Swirl’ – Photo courtesy Daniel Leonard

  • ‘Starry Starry Night’ by Walter’s Gardens. (Pictured) This cultivar combines dark purple to black leaves with swirled pale and dark pink flowers.  It has performed very well in my landscape and if I could only grow one, this might be it.
  • ‘Lord Baltimore.’ The classic, large growing cultivar with bright red flowers that is widely available and easily found.  An oldie (introduced in 1955) but a goodie.
  • ‘Midnight Marvel’ by Walter’s Gardens. A “hot off the press” new cultivar that is currently difficult to find due to popularity, though some online outlets have them available in small sizes.  This one is worth your patience.  Sporting deep red blooms on near black foliage, there’s nothing else like it in the landscape.

In addition to being gorgeous plants, Rose Mallows are extremely versatile in the landscape and could not be easier to grow.  Because the size varies so greatly (from the diminutive 30” tall ‘Luna’ series to the 8’ tall unimproved species), there really is a place for one in every garden.  I like to use the smaller cultivars in large containers to facilitate moving them around where their floral display has the greatest impact or to create a tropical effect where in ground plantings are not an option (pool decks, patios, etc).  The larger cultivars make spectacular specimen plantings in perennial and shrub beds and even make a really dense, striking hedge (just know they disappear in the winter).  Be sure to give them as much sun as possible, as this will enhance the number of flowers on each plant and darken the foliage on the cultivars with purplish/black leaves.  Too little sun will result in fewer flowers and lighter green foliage.  As wetland plants, Rose Mallows enjoy regular water, either from rainfall or irrigation; they will let you know when they need it – their large leaves readily wilt under drought stress, somewhat like Hydrangea.

For low-maintenance, native, pollinator friendly, cold-hardy tropical color, you need look no further than Rose Mallow.  These perennial shrubs come in all sizes and colors and fit any landscape!  Look for the above listed series and cultivars at better garden centers and online retailers and enjoy the oohs and ahhs elicited when people first get a glimpse of Hardy Hibiscus in your landscape!  Happy Gardening!

 

The Grass is Getting “Hungry”

The Grass is Getting “Hungry”

(UF/IFAS photo Thomas Wright)

Northwest Florida’s weather patterns can present challenges to maintaining a health lawn. Heavy rains promote fast growth and relentless sunshine causes lawns to fade.  In the last 200 days we have received at least 68 days of rain.  While the rest of Florida was experiencing record drought, the Panhandle was experiencing torrential downpours.  With every drop of rain your spring fertilizer is being metabolized by the lawn, reducing how many nutrients remain in the soil.  Even the best slow-release fertilizer will only last 3-4 months.  The message is: “It’s time for more fertilizer.”

A healthy lawn is an important component of the urban landscape. Not only do lawns increase the value of a property, they also reduce soil erosion, filter stormwater runoff, cool the air, and reduce glare and noise.  A healthy lawn effectively filters and traps sediment and pollutants that could otherwise contaminate surface waters and groundwater.  Lawns require nutrients throughout the growing season to stay healthy.  In Northwest Florida the growing season is typically April to October.

Proper fertilization consists of selecting the right type of fertilizer and applying it at the right time and in the right amount for maximum plant uptake. The type of fertilizer should be based on a soil test, available through UF/IFAS Extension. The timing of application and amount of fertilizer is dependent on the research-based recommendations for the grass species and the fertilizer analysis of the product being used.

Chart excerpted from Florida Friendly Landscaping publication

Select only a fertilizer that states that the product is for use on residential turf. Do not use a fertilizer meant for flower or vegetable gardens on lawns. By Florida Administrative Code, Rule 5E-1.003, the Urban Turf Rule requires that the fertilizers being applied to residential lawns are labeled for the site and the application rates be followed.  Typically, these products will contain both slow-release nitrogen and low or no phosphorus.  Slow-release nitrogen will provide a longer-lasting response from the grass and reduces the potential for burning. For more information on the Urban Turf Rule go to: http://www.edis.ifas.ufl.edu/pdffiles/EP/EP35300.pdf.

With frequent rain the soil is also losing iron. Keep in mind that the green fading to yellow appearance in your lawn may be an iron deficiency.  Before applying your summer fertilizer put out a liquid chelated iron.  It will improve the health of the lawn while you are trying to find a dry day to fertilize.  While it is necessary to water in fertilizer with ¼” of water to reduce burn potential and volatilization, never apply fertilizer when heavy rain is expected.  The rainfall over ¼” can encourage runoff and/or leaching of that fertilizer, which can be costly and environmentally harmful.

Mowing Your Lawn Correctly

Mowing Your Lawn Correctly

Northwest Florida has experienced an enormous amount of rain this summer. The western panhandle has received over 29 inches of rain since the beginning of May according to the Florida Automated Weather Network station at the West Florida Research and Education Center in Jay, Florida. That is 44% of average annual rainfall in less than two months. All of this rain has probably thrown off the normal lawn mowing routine. It is hard to get out and mow the lawn when its pouring buckets or the lawn resembles a swamp. With all of this in mind, there are a couple of mowing pointers that would be useful to implement to address the out of control lawn growth and the challenges posed by not being able to stick to normal mowing schedule.

  • Always attempt to mow at the IFAS recommended height for your species of turfgrass. The recommended heights are determined by how quickly the species grow in our climate. The chart below shows the best heights at which to mow your lawn. The fine textured zoysiagrasses are not listed but should be mowed at 0.5 to 1.5 inches. Check the lawn mowers mowing height by measuring the distance from the ground to the bottom of the mowing deck on a flat surface.

From Mowing Your Florida Lawn: http://edis.ifas.ufl.edu/pdffiles/LH/LH02800.pdf

  •  When you do get out to mow, never remove more than 1/3 of the leaf blade. If you cut to short you will “scalp” the turf and cause a brown look on the lawn. This can be damaging to the turf and allow for weeds to get established by exposing the soil to the sunlight. What is taking place more in northwest Florida is not mowing frequently enough and cutting off excess growth due to the rain. This also can cause scalping so it is very important to mow frequently enough to only remove 1/3 of the leaf blade.

A zoysia lawn that has been “scalped” after excess growth and infrequent mowing. (Photo Credit: Blake Thaxton)

Other practices such as keeping your mower blade sharp, mowing in different directions, and leaving clippings on the ground will help keep a healthy Florida lawn. Please see more information about mowing correctly in Florida in the University of Florida/IFAS Extension publication: Mowing Your Florida Lawn