New Zealand spinach has a mild flavor, flourishes in the heat, and can serve as a nutritious summer salad. Photo by Forest and Kim Starr.
If you’ve ever tried growing lettuce (Lactuca sativa), true spinach (Spinacia oleracea), or crops in the cabbage family (Brassica spp.) in late spring or summer in the subtropics of Florida, you know that our extreme heat can make it difficult. Between bolting leaves, fungal diseases, insect pressure, and poor germination, it can be quite a challenge to keep greens on the dinner table all year long.
Fortunately, there are a few greens that – while less well known – can take our Florida heat and are relatively easy to grow. Some of these greens include New Zealand spinach, Malabar spinach, and perpetual spinach. They are frost sensitive and prefer well-drained, slightly acidic soil and require regular watering, but they don’t need a lot of fertilizer or special attention. Additionally, they are resistant to most pests and diseases.
New Zealand Spinach
New Zealand spinach tastes similar to true spinach but can stand up to the Florida heat. Photo by Forest and Kim Starr, Starr Environmental, Bugwood.org.
New Zealand spinach (Tetragonia tetragonioides) is a leafy green that is native to New Zealand, but it is well-adapted to warm climates such as ours. It grows one to two feet in height and branches two to three feet across. In the kitchen, it is known for its mild, slightly salty flavor, and it is a great source of vitamins A and C, iron, and calcium.
New Zealand spinach germinates slowly, taking two to three weeks to sprout. Soaking seeds for 24 hours directly before planting can help them along, but be patient, and keep the planted area weed free.
Sow seeds a quarter-inch deep, two inches apart, and water well, keeping the soil moist but not waterlogged. Once germinated, thin to eight to 12 inches apart. After the plant has grown about a foot, harvest a few tender leaves off of each branch, making sure enough leaves remain so the plant can continue to photosynthesize and grow.
Read the UF/IFAS publication Spinach, New Zealand to learn more about growing New Zealand spinach.
Malabar Spinach
Malabar spinach (Basella alba and B. cordifolia) is a fast-growing leafy vine native to tropical South Asia. It is known for its thick, succulent leaves and its slightly lemony flavor. It is a good source of antioxidants, vitamins A and C, iron, and calcium.
Support fast-growing Malabar spinach vines with a trellis or stakes. Photo by Molly Jameson.
Like New Zealand spinach, Malabar spinach is vulnerable to frosts and grows well in hot, humid conditions. Wait until soil temperatures reach 65°F to 75°F to sow or wait at least three weeks after the last frost date. Typically, in our area, it does best sown from mid-April through early June.
Sow seeds a quarter-inch deep, two inches apart. Also, like New Zealand spinach, Malabar spinach can take two to three weeks to germinate, so soaking seeds for 24 hours prior to planting is recommended. Once planted, keep the area weed free and well-watered, but not waterlogged.
After germination, thin the sprouts out so that they are spaced 12 inches apart. In optimal conditions, the plant can reach maturity in 70 days. Vines will continue to grow to 10 feet or longer and will benefit from a trellis, a fence, or stakes to assist in climbing. Harvest the leaves and young stems and prune back any overlong vines.
Perpetual spinach is related to Swiss chard and beets, but it is more “spinach-like” in flavor. Photo by Baker Creek Heirloom Seed Company.
Perpetual spinach (Beta vulgaris), or spinach beet, is a leafy green that is the same species as Swiss chard and beets, but tastes more like a true spinach and is known for its mild, slightly sweet flavor. It is a great source of vitamins A, C, and K, as well as calcium, magnesium, and iron.
Perpetual spinach can tolerate cooler temperatures than New Zealand and Malabar spinach, but it also grows well in warm weather and can continue to produce throughout the growing season.
Sow seeds a half-inch inch deep, two inches apart. Water well and keep the soil moist but not waterlogged. Again, be patient, as like the other heat-loving greens, perpetual spinach can take up to two to three weeks to germinate.
Once the plants have sprouted, thin them out so that they are spaced six to eight inches apart. Begin harvesting by cutting leaves at the base of the stem. If the plants get too big or the leaves begin to taste bitter, cut the leaves back to about three inches above the soil and they will produce new, tender leaves.
While these heat-loving greens do not taste the same as lettuce, true spinach, kale, or collards, they are incredibly versatile in the kitchen and have a unique flavor profile. They can be eaten raw in salads, or they can be cooked in a variety of dishes. For example, New Zealand spinach can be sautéed with garlic and lemon juice, while Malabar spinach can be used as a green in a delicious stir-fry. Perpetual spinach can be used in soups, stews, casseroles, and salads.
Other heat-loving greens to try out in the garden include Okinawa spinach (Gynura crepioides), longevity spinach (Gynura procumbens), and Surinam spinach (Talinum triangulare).
If you are looking to keep homegrown greens on the dinner table this spring and summer, give heat-loving greens a try! They are easy to grow, resistant to pests and diseases, and are great additions to many dishes.
The UF/IFAS Extension Bay County Pollinator Garden is the proud recipient of a Little Free Library built, stocked, and installed by the Bay County Library Foundation. We were incredibly fortunate the foundation had the perfect box designed and painted by local artist Heather Clements just waiting for the perfect place to be installed!
You might be asking yourself, how does a Little Free Library work? It’s very simple, if you want a book you take one and if you have a book to donate you leave it in the box. Our box includes books for all ages and reading levels including children’s books in English and Spanish and of course gardening and wildlife topics. As people exchange books the titles and topics will change and evolve over time.
If you are in Panama City I hope you will take a moment to pick out a book and enjoy our demonstration gardens at 2728 E. 14th Street, Panama City and visit the virtual garden for educational information about the garden inventory.
Looking for a Little Free Library near you or Interested in starting one? Visit https://littlefreelibrary.org/start/ or contact your local library to find out more information.
A mixed vegetable garden. Photo Credit: eXtension.org.
It doesn’t get much better than eating fresh vegetables out of your own garden. I guess you could add a beverage to the mix to improve the experience. A dry chenin blanc would probably go well. Unfortunately, this month’s Gardening in the Panhandle LIVE steered clear of wine as a topic, but the featured agents did focus on vegetables.
Container Gardening
Size does matter when it comes to container gardening. Think about the full grown size of the plants you plan to grow when selecting a container size. For most vegetables, 10 inches wide by 10 inches deep is sufficient, but you can grow in much larger containers. The larger the container, the more room the roots will have. For more information on gardening in containers, check out the articles “Don’t Think You Have a Green Thumb? Try Container Gardening!” and “Container Gardens for Outdoor Spaces”.
If you have a really deep container and don’t want to spend the money on potting soil to fill it up, then you’re kind of out of luck. Rocks or other materials placed in the bottom of containers will create a perched water table. So basically, you’re creating a shallower container by putting materials other than potting mix in the bottom. The physics on this topic is better explained in “Rocks in Pots: Drainage or Perched Water Table Problems?”.
It’s best to start with new potting soil each year. Especially if you plan to grow the same plant species/families in the same containers. However, if you do plan to reuse potting soil, make sure to mix it up a bit with a trowel or dump it out and put it back in the container or another container. Also, choose a different crop than what you grew in the soil the previous year. Here’s an interesting publication on growing squash in recycled potting soil.
Raised Beds
Raised beds are a great option if you live in an area with poorly drained soil or with a soil that doesn’t hold nutrients. They also can be built on legs like a table to save your back some stress. More information on build a raised bed can be found in the article “Building Raised Beds”.
Vegetables need space to grow whether they’re planted in the ground, in a small container, or in a raised bed. Recommended varieties for container gardening and spacing recommendations can be found in this container gardening fact sheet from UF/IFAS Extension in Leon County.
Who says you can’t landscape with vegetable plants and fruit trees? Vegetables such as cabbage and kale can add a depth of color and texture to your annual flower beds. And blueberry bushes and citrus trees have beautiful blooms that bees love.
Trellises can be easily built and attached to raised bed gardens. Pole beans and Malabar spinach are just a couple examples of vegetables that need something to climb on. Lettuce and other small vegetables can be grown vertically in different hydroponic systems.
Plant Selection
Some seeds can be sown directly into the garden while others should be started in trays and transplanted. More information on sowing seeds and timing can be found in the Vegetable Gardening Guide. Just make sure to check out the tables at the end of the guide.
Some plants are more tolerant of salt air and salt water. This doesn’t mean you can water these plants with the Gulf of America, but they will tolerate a little bit of salt. A list of salt tolerant vegetables can be found in “Salt Tolerant Vegetable Gardening”.
A number of cherry tomato varieties produce a big crop fast and over a long period of time. A list of recommended cherry tomato varieties can be found in this article on cherry tomatoes.
There aren’t a lot of options for perennial vegetables in North Florida. A perennial vegetable that can be grown here, taro, can be invasive. If you plan to grow this vegetable, please consider growing it in a container. Fortunately, we have a lot of options for perennial fruiting crops. More information on growing fruit trees can be found in the publication Dooryard Fruit Varieties.
Blackberries grow well in North Florida. You may want to try the thornless varieties ‘Freedom’, ‘Traveler’, ‘Osage’, and ‘Ouachita’. More information on growing blackberries can be found in the publication “The Blackberry”.
Some vegetables grow well in the shade. The “Veggies and Herbs Made in the Shade” publication includes a list of shade loving vegetables and herbs along with growing tips.
Community gardens provide a place to garden for people that may not have space at home. Gardening in these plots also gives people a place to meet their neighbors. Information on starting a community garden can found in the publication “Starting a Community Garden”.
Homegrown beets don’t taste anything like the ones your grandmother gave you out of a can. More information on growing beets and other root crops can be found in the Root Crop Chapter of the Vegetable Production Handbook of Florida.
Vine borers and leaf footed bugs are some of the most damaging pests to a vegetable garden. Planting early in the season can help avoid these pests, but if you’re too late on planting then you might want to give some natural products a try. The publication “Natural Products for Managing Landscape and Garden Pests in Florida” provides some good pointers on controlling these and other insect pests.
Squirrels and other wildlife can also be pests in the garden. Deterrents can help keep these pests out of the garden.
Ants don’t usually mess with your vegetables, but they can be a nuisance when working in the garden. Fire ant management information can be found in the publication “Managing Imported Fire Ants in Urban Areas”.
Squash and other cucurbits don’t last long in wet areas. They don’t last long on the vine in the first place. Growing on plastic mulch, or even pine straw, can help these vegetables stay dry. You may also want to consider building a trellis for vining cucurbits. Also, make sure to harvest in a timely manner. Squash that overripen on the vine attract insect and disease pests and just don’t taste very good.
Weeds can compete for nutrients with your crops and don’t look very attractive in the garden (or anywhere). If you’re tired of hand weeding, the Vegetable Production Handbook of Florida lists herbicide options by crop.
Past episodes of Gardening in the Panhandle LIVE can be found on our YouTube playlist.
About a year ago, one of my regular blog readers asked if magnolia trees (Magnolia grandiflora) had any particularly redeeming qualities. The one in her yard was constantly dropping leaves and seedpods, and she was tired of it. Little did she know, she had stepped into the domain of an absolute devotee of the magnolia tree. I told her that as a child of the Magnolia State (Mississippi) with the new magnolia-centered state flag flying from my front porch, it was my sworn duty to defend this magnificent symbol of southernness. Well, maybe I wasn’t so dramatic, but I definitely took on the challenge.
Magnolia trees produce large cones/seedpods that are filled with wildlife food. Photo credit: Carrie Stevenson, UF IFAS Extension
First, I do empathize with the constant leaf dropping. We have a large, beautiful magnolia tree in our front yard, and it drops its thick leaves year-round. We just rake them into a natural mulch pile around the base of the tree, though. As for the seedpods—those I have learned to be wary of. A couple of summers ago as I walked to my mailbox, I didn’t see one on the curb, then promptly rolled my ankle on it and landed face-first onto the road. After massive swelling and bruising on my foot, I finally went to a doctor to discover I’d managed to tear a tendon. So, tread carefully around the dropping seedpods!
The sturdy branches of our magnolia tree have supported a swing for over a decade. Photo credit: Carrie Stevenson, UF IFAS Extension
But aside from that, it’s all positives. A Southern magnolia is as sturdy a tree as you could hope for—it is consistently ranked as one of the most wind-resistant trees in the landscape. Their thick, dense, upright trunks and the overall pyramidal shape allows the wind to whip around them, rarely causing damage. In fact, the only damage we’ve had to our tree was when a weaker tree fell on our magnolia and knocked some branches off. Eighteen years after Hurricane Ivan, it’s filled in and you’d never know it lost branches. Ours was planted 50 years ago to celebrate the birth of the previous homeowners’ son, and has been a source of shade and relaxation (we have a great swing hanging from it) ever since.
The broad, open shape of the fragrant magnolia bloom co-evolved with its beetle pollinator millions of years ago, before bees existed! Photo credit: UF IFAS
Like many other trees, magnolias have medicinal uses. The bark of a related magnolia species has been used in traditional Asian medicine to treat “anxiety, asthma, depression, gastrointestinal disorders, headache, and more” and our North American varieties were once used as an antimalarial drug. Modern research has shown seed extracts are effective in maintaining sleep and body temperature, as a sedative, and in reducing the intensity of epileptic seizures. As always, never attempt to use a plant-based home remedy without consulting a physician!
To me, nothing quite says springtime like a magnolia blossom. As buds, they are thick and velvety, completely covering the trees with pops of bright white. Once they bloom, these large (up to 8” wide) saucer-shaped blossoms give off a lovely fragrance, attracting pollinators. Interestingly, magnolias are such an ancient species that they evolved (in the Cretaceous period) before flying insects like bees and butterflies existed. Therefore, magnolias are pollinated by flies and flightless beetles, which crawl from one flower to the other, relying on their sense of smell to guide them. Because beetles are chewers, the flowers and leaves co-evolved to be thicker and tougher to offset and survive the bugs’ messy eating habits. Once the flowers have gone, the fuzzy grenade-shaped cones/seedpods grow on the trees. After the seedpods fall, they open to reveal brilliant red seeds. These have significant wildlife value, as songbirds, squirrels, deer, wild turkey, and quail eat the seeds. This time of year, many people use the waxy, deep green leaves for seasonal décor—magnolia wreaths are quite popular, especially in the south. Many people make their own, but companies often sell them for hundreds of dollars apiece!
Magnolia macrophylla ssp. macrophylla (Bigleaf Magnolia) Photo credit Danny Schissler
In our area, the Southern magnolia is only one of several beautiful native specimens of the Magnolia genus. In freshwater wetlands, the slightly more petite sweet bay (Magnolia virginiana) is easily recognizable by the backs of its leaves, fluttering a silvery gray in the wind. One of my very favorite trees is the bigleaf magnolia (Magnolia macrophylla) which boasts mind-boggling leaves that can be over 2 feet long! In his travels throughout the United States in the late 18th century, explorer and naturalist William Bartram described the leaves as “an expanded umbrella, superbly crested with a silver plume.”
The sweetbay magnolia is easily recognizable by the silvery gray color on the backs of its leaves. Photo credit: Dan Gill/LSU AgCenter
Magnolias may be so common as to seem unremarkable to many, but they are a hardy group of trees who have survived on the planet since dinosaurs roamed the earth. And that’s about as redeeming a quality as you can get. To learn about other magnolia varieties that work well in our area, check out this publication from UF IFAS Gardening Solutions.
Written by: Muhammad Adnan Shahid and Mujahid Hussain
What made this freeze event damaging?
The duration of temperatures below freezing determine the amount of damage to citrus plants. In January 2023 the temperature dropped down to 17 F and stayed at that temperature for a longer time than in recent years. Unlike 2022-23, during the winters of 2013-14, the recorded low temperature was 18 F for half an hour. Similarly, during 2014-15, the temperature touched 19 F and stayed only for 15 minutes. Except for these two winters, in the past 12 years, temperatures never dropped below 20 F. What made this freezing event of December 2022 devastating is the long freezing hours between 17-20 F for 11 hours and even more the temperature stayed for about an hour at 17 F (Fig. No.1).
Fig. No.1. Shows the temperatures (17-20 F) duration during the past winters of 2011-2023. The temperature data is retrieved from Florida Automated Weather Network, UF/IFAS Extension Service (https://fawn.ifas.ufl.edu/). During these years, according to this data, only in December 2022, the temperature fell to 17 F which caused severe damage to the citrus in North Florida.
Symptoms After Freeze
Early Symptoms
The duration of appearance of symptoms after freezing was different for different citrus varieties. Even within the same varieties, the age of the plant and the rootstock are also factors that determined the duration of the appearance of symptoms. For example, in the UF 950 rootstock evaluation block at North Florida Research and Education Center in Quincy, the symptoms appeared on young UF 950 plants on Sour orange rootstock after 24 hours and after three days the plant completely turned brown.
Fig. No. 2. Shows the effects of freezing on UF 950 on Sour orange rootstock after day 1 (a) and day 3 of freezing (b). The young plants completely turned brown after three days of freezing.
However, a few symptoms that appeared after about 24 hours of freezing were similar on all plants regardless of age, variety, and rootstock. These include the blackening of new leaves and branches, hardening and yellowing of leaves, and formation of greenish and brownish patches (Fig. No. 3). The leaves of old citrus trees also became curly, stunted, and yellow. During the freezing event, the fruits on the trees became hard due to the nucleation of water.
Fig No. 3. Symptoms after 24 hours of freezing.
Low temperatures below freezing point cause the formation of ice crystals inside the plant, particularly in leaf tissue, causing a damaging effect of cell walls, and leaves appeared water-soaked upon thawing when temperature rose above the freezing point (Fig. 4).
Fig 4: Water-soaked leaves due to the ice crystals formation and their thawing inside the tissues.
Late Symptoms
One week after freezing, leaves started curling – turning brown and dry. At this stage, both leaves and fruits dropped very quickly, within a week giving plants a bush like appearance (Fig. No. 5 and 6). The fruits that remained on the tree developed multiple symptoms depending on the varieties. Fruits of some varieties formed micro-pits on the peel, however, the fruits of other varieties showed patterns of bright orange and yellow colors (Fig. No. 6a). The rotting leaves and fruits also attracted ladybug beetles, consequently this increased populations of other insects in freeze damaged citrus groves. You should keep in mind that the fruits that have been harvested after freezing need extra care as these fruits are more prone attacked by rotting fungi.
Fig. No. 5. Late symptoms of freeze damage on citrus trees.
Fig. No. 6. Fruits turn black and fall from the tree after freezing.
Fig. No. 7. The freezing caused the fruit’s peel to form patterns of bright orange and light-yellow color on the fruits (a). The rotting of leaves and fruits produces an odor after freezing that attracts ladybug beetles (b).
Bark splitting or cracking is a late symptom of freeze damage. Bark splitting or cracking will mostly be seen on stem and branches directly exposed to the sun. Bark splitting starts when sun light increases the temperature on the surface of the bark during daytime, but temperature drops after sun set resulting in unequal shrinkage and contraction of bark and inner plant tissues (Fig 8). Dropping of leaves and fruits is a good indication of plant survival, but if leaves dry while attached and don’t drop then it’s the sign of severe damage to internal tissue with a low chance of plant recovery (Fig 9)
Figure 8. Bark splitting and cracking as a consequence of freeze damage.
Fig 9. Tree with dried leaves still on the branches – it is indication of sever freeze damage to internal tissues
Recovering Plant After Freeze Damage
The recovery of plants is entirely linked to the level of damage to the plant internal tissues during the freeze event. Freezing damage can exacerbate the plant’s health, thereby minimizing the recovery of the plant. However, plants can recover if the internal cells (cambium and xylem and phloem) are alive enough to regenerate the branches. After an extreme freeze event, like what happened in December 2022, some citrus plants will recover in spring due to the presence of living cells in the branches and stems, but if the internal transportation system is damaged, the plant again starts to die back for the next several months. You should not apply any recovery techniques immediately after the freeze event. The best strategy is to wait for the spring to see if plants are giving any indication of recovery and observe their growth at least till May-June.
Fertilization
It is true that after damage, plants require nutrients to regenerate and grow but the application of nutrients is critical as excessive fertilization can also increase the risk of damage. Do not apply any fertilizer until new growth starts in spring. Fertilizers should be applied frequently, but rates should be decided depending on the degree of damage. The plants that are severely damaged will not be able to produce fruits in the next season therefore, the rate of fertilizer should be lowered to promote a slow recovery, as the damaged plants will not be able to uptake all applied nutrients due to slow water flow caused by minimum transpiration rate in the absence of leaves. In this case, any excessive application of fertilizer can cause toxic effects that can further halt the recovery of plants. The application of micronutrients is also important for the recovery of plants.
Plant Protection
Care should be taken to protect the plants from pathogens, insects, and weeds to enhance recovery. Citrus plants regenerate in the spring and aphids and whiteflies like to attack the young leaves, branches, and shoots. Therefore, an effective plant protection plan should be devised that includes the application of insecticides and fungicides. In general, one to two applications of fungicide should be planned along with nutritional spray to prevent infection on new growth. Removal of all fruit from freeze damaged trees is also important for quick recovery (Fig 10)
Fig 10. Freeze damaged stems with living and non-living tissues. Stem with living tissues will recover easily as compared to those with dead tissues
Fig 11: Fruit are removed from freeze-damaged tree
Pruning
Pruning should be avoided because it is not clear how much damage has been done to the plant. Pruning should be delayed until spring or summer. Ideally, pruning should be done on living wood to make sure that all the damaged parts have been removed. If the citrus tree has been damaged below the rootstock/scion union, it is better to re-graft the new scion on the rootstock instead of pruning. Pruning of trees that have been damaged below the scion union will result in the generation of rootstock. Therefore, re-grafting the plant or replanting is the best option. The Fruit Physiology Lab at NFREC-Quincy is developing tissue imaging techniques for quick estimation of percentage of tissue damage in freeze affected citrus tree shoots and roots.
Irrigation
Irrigation after freeze damage should be reduced. Damaged plants do not uptake as much water as healthy plants, therefore, excessive water in roots can cause the nutrients to move away from the plants and even can cause suffocation for young emerging roots. It is not recommended to completely cut off the water supply, because this can further damage the plants.
Research
The Fruit Physiology Lab at NFREC-Quincy is developing tissue imaging techniques for quick estimation of percentage of tissue damage in freeze affected citrus tree shoots and roots. A series of preliminary studies on the use of growth hormones (brassinosteriods, abscisic acid and jasmonic acid) and nutrients (silicon, K and Zn) to improve the cold hardiness is in progress. Preliminary data indicates that the use of growth hormones and plant beneficial nutrients has the potential to reduce freeze damage (Fig 12), but more detailed research and validation in large scale field trials is required. Postdocs and graduate students in The Fruit Physiology Lab at NFREC-Quincy are fully engaged with different research projects to improve the cold hardiness in citrus by hormonal and nutritional therapies. Recently, the lab got a funding to study new scion and rootstock combinations with high cold tolerance.
Fig 12. Effect of Silicon on cold hardiness of citrus plants sprayed with 100ppm of silicon one week before exposed to freezing temperature (-6 C) in programed freezing chamber
Conclusion
Florida has faced record freezing this winter season with recent events that occurred in the last week of December 2022 causing severe damage to citrus trees in North Florida. Citrus growers in South Florida are already fighting with the HLB disease and freeze damage in the North has added to the damage to the citrus industry in Florida. Careful planning and proper care can help damaged citrus trees to recover and start fruiting again. Trees with little damage to their woody parts will recover soon and start fruiting in the next season. However, the trees with more damage to their woody parts will take two or more years to recover enough to start fruiting. Therefore, proper assessment of the damage is important and recovery strategies should be devised according to the degree of damage. Recent freeze events gave us a big message that microsprinklers are not enough freeze protection for established trees. There is also a need to identify growth hormones, nutrients, or combinations of which can improve the cold hardiness of upper plant parts. In addition, exact estimation of recent freeze damage won’t be accurate until April-June.
