Creating a Climate-Resilient Garden in North Florida

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I was inspired to produce this podcast episode because we’ve been in a drought for a couple of months. And then, right as I was preparing to release it, severe thunderstorms dumped an inch-and-a-half of rain on our area. It might wet and mucky out when you listen to us talk about gardening in dry conditions, but that’s a big part of the story, too (Also, one storm doesn’t end a drought).

North Florida gardeners have had to contend with long droughts and higher temperatures, but also extreme weather events, hard freezes, and the occasional ice-scape. Today, we’re not exclusively talking about creating a drought-resistant garden, but a resilient garden. How can we best protect our plants from all of it?

Our guest is Mark Tancig, the Commercial/ Residential Horticulture Extension Agent for the UF/IFAS Leon County Extension. IFAS stands for the Institute Of Food And Agricultural Sciences, at the University of Florida. As Mark explains, UF conducts the research, and extension offices in each Florida county connect it to local residents.

Mark provided a reading list of further resources, to which you’ll find the links below. You can also contact your local extension if you have a specific question or problem. If you’re one of our out-of-state readers, every state has a land grant university and its own extension system.

Coast to Canopy blog posts are curated transcripts. My notes appear in italics.

1. Plant Selection

Mark Tancig: We talk a lot about Florida friendly landscaping principles… number one is “Right Plant, Right Place.” And so we’re always encouraging people to really consider their site.

Native plants, adapted to your setting, will need less water and fertilizer to grow. Within Florida, and even within Leon County, there are multiple ecosystems with different soils.

Leon County, we’re a little different, right? A lot of Florida is sand. It’s beach sand. I was just in South Florida visiting recently, and it’s just deep, deep sand. Where, in North Florida, we have these clays that give us a little bit of a different soil texture and soil water holding capacity.

When it comes to plant selection, native plants are usually going to be a lot more resilient and tolerant of the kind of the variation in the climate. But it’s important to remember where you are and what was native to your particular area. Lots of native species, coontie a really good example of a native plant, but it’s native to South Florida. They may not particularly be native to Leon County or your particular part of Florida.

So it’s important to do that little research, do some observations, go to local parks, see what’s growing easily there without any kind of help and kind of try to get some ideas based on that local environment around you.

Generalist plants

Mark Tancig: If you try to grow trillium in your middle Tallahassee, downtown lot, it’s going to struggle. Where some folks, they just have them popping up in their backyard because they are on the edge of a ravine forest type of thing.

It’s great to use natives. But again, some of these real are very kind of specialty native plants are going to be harder to pull off. So, the generalist natives that do well across several different conditions, soil types, that kind of thing [is what works best in most yards].

As an example, Mark talked about the Monarch Milkweed Initiative at the Saint Marks National Wildlife Refuge, which we visited in 2019. They had been trying propagate sandhills milkweed (Asclepias humistrata), a specialist that grows in arid, fire-dependent sandhill habitats. Over twenty species of milkweed are native to Florida, in a variety of habitats, from wetlands to ravine edges to longleaf pine woodlands. However, I only regularly see three native species in nurseries: pink swamp milkweed (Asclepias incarnata), butterflyweed (Asclepias tuberosa), and aquatic milkweed (Asclepias perennis).

As the climate warms, should we start using plants from warmer areas?

Mark Tancig: One thing we know about climate change is that it’s happening, first of all, and that it’s variable. So, we’re in March here in Leon County. We had a pretty cold winter last year. We had ice on the ground for several days. And now within two weeks of being in the 30s at night, we’re having like 90 degree days, record heat. And then, in a couple days from now, we’re supposed to go down in the 30s again.

The variability is all over the place. And so, the one concern about picking things that are a little more to the south of us is still, we’re going to get cold snaps that are going to knock them back… you can often find what’s the range of the species that you’re looking at, and making sure that we’re a little bit in the middle.

Some plants you might want to avoid are actually species where the range just goes a little bit south of us. Dogwood trees are a really good example of a native species that are kind of getting stressed out by climate change and the warming temperatures. We’re already kind of at the southern end of their range. And so, they’re kind of getting pinched out right by this warming climate.

2. Build healthy soil

Mark Tancig: A lot of our soils, they’re very low in organic matter… things like compost, things like just leaving a nice mulch layer to slowly allow it to break down and create organic matter.

That’s going to be really, really important, starting with a good base of high quality soil.

In nature, decomposing leaves and wood form a layer of topsoil, which feeds nutrients to plants and helps retain water closer to the surface of the soil.

Mark explained this in more detail in a previous segment on Florida soils. Soil is formed from weathered rocks – inorganic matter. When rocks are weathered into larger grains, it forms sand, while soils with the finest particles are clays. Florida soils are sandy, which means water passes through them quickly. Even the red soil of our area contains more sand than clay; it is known as Orangeburg sandy loam. Water passes through it more slowly than pure sand. Organic matter helps build a healthy layer of topsoil.

Living, breathing soil

Mark Tancig: Our management practices affect soil health… if we can minimize how much we disturb the soil, and keep it covered with plants, with mulch, that’s going to help.

Because if we want good soil health, we want life in the soil, right?

We want microbes. We don’t want a lot of compaction. So, especially in a vegetable garden, but even in a pollinator flower garden, trying to minimize how much you’re walking in there, because plant roots. We always think of plants [giving] off oxygen, but it’s really important for plant roots to actually have access to oxygen, because they’re burning all those carbohydrates. To grow roots, they need air.

We want it to be alive. One great way to do that is organic matter. Again, organic matter is the answer to a lot of problems when it comes to soil health. Incorporating compost, especially where we’re trying to grow vegetables and fruit crops. But even in the landscape setting, letting leaves lay.

Think of the forest, of how it builds a healthy soil. Leaves fall, they rot. And that recycles those nutrients, because of those microbes. And it feeds to that organic matter component. Another thing is to think of – your fungicide use would be probably the biggest one, fungicide and insecticides.

A lot of microinvertebrates are doing a lot of this nutrient cycling. And sometimes we have to use these pesticides, if we have a fungus in the landscape or an insect taking out something, but trying to really be thoughtful and selective on how we use them.

But with soil health, let’s kind of let it be. Let’s add organic matter. Let’s not put a bunch of pesticides on it, and reduce compaction.

Mycorrhizal fungi – Building a Wood Wide Web with Tough Love

The following applies to the places where we try to build habitat with native plants. Fungal networks develop in undisturbed soils, to the benefit of your plants.

Mark Tancig: Mycorrhizal fungi is really cool, a lot of research recently into this and how it works. And… if you’re watering and you’re fertilizing the plants, they found don’t make a connection to the mycorrhizal fungi because they have all the water and the nutrients they need. So they’re not going to give up any carbohydrates to this fungi.

But, as when we’re talking about a resilient landscape, these connections would become really important, right? The plants give a little sugar to the fungi, and then the fungi help expand that root network, basically, and help provide water.

And especially phosphorus was a big nutrient that it helps provide to the plants.

3. Mulching protects and build soil

Mulch covers the soil, protecting it from the sun, retaining moisture, and adding organic matter that will decompose and build the soil.

Mark Tancig: We do tell folks to stick with natural mulches.

You can find rubber or you can find some other things. We try to steer people away from that because they don’t break down and give us that benefit of organic matter. We also actually tell folks to stay away from cypress mulch because of the problem you stated, [that] they’re cutting down these amazing wetlands to make mulch.

Another good alternative would be pine bark nuggets. So the chunky pine bark nuggets, the research at UF has actually shown that it’s the punky, chunky pine bark nuggets and the pine straw that do the best for weed control.

Some municipalities give away the landscape mulch, where they’re picking stuff up the side of the road (Yard waste). That stuff is usually free, which is a nice little benefit. But it’s usually chopped up a little finer… So the weed control might be less. It is going to add to organic matter quicker because it’s finer.

The risks and benefits of lighter mulches

Mark Tancig:  Sometimes, if you have a native wildflower patch, if you want these things to reseed, that’s where you may not want to use the chunky pine bark nuggets. If you have a garden that you want to reseed, you want to try to keep a very thin layer of mulch there so that actually those seeds can get that into the soil.

Lighter mulches, like pine straw or fallen leaves, provide ground-nesting insects easier access to soil. Most of our area was historically covered by longleaf or (in and around Tallahassee) shortleaf pine, and bees and other insects evolved with pine needles over bare soil.

Mark did mention that mulch from tree pine straw farms sometimes contains Japanese climbing fern spores. And, as we learned in our last episode of Coast to Canopy, many of those farms kill off their ground cover to more easily harvest pine straw.

4. Water: Less is More, Depending on the Plant

Mark Tancig: With your vegetable plants, I always tell folks you want those to remain happy, right? You don’t want them to start wilting on you because… that’s going to reduce your yield.

Ornamental plants… let them wilt a little bit.

They can kind of work a little bit harder. That’s actually good for them because, in those times of stress for them, they’re actually going to put more input into roots. And they’re going to try to grow their roots out more, and deeper. That’s going to give them a little bit more resilience over time.

If you baby those ornamentals for a long time, and this includes your turf grass, they don’t work too hard to put out deep roots. And so we get a little bit of a dry spell, or your irrigation system doesn’t work for a little bit, and that’s when they really start to have problems.

The stress then leads to other problems: insects, disease, where you kind of you potentially lose them altogether.

Florida native plants are adapted to sandy soils and fire. They have evolved extensive root systems, which capture more water as it passes through sandy soils. For many grasses and herbaceous species, their deep roots allow them to regrow quickly after a fire.

5. Observe Your Plants and How They Respond to Stressful Conditions

Mark Tancig: I love to talk to people about just getting out into their garden, and getting out into nature in general, and just being observant. Just the basics of science, right? Being out there and making observations.

Spend time in your garden at different times of the day.

Check it out in the morning, check it out in late afternoon, even go out there at night sometimes and see what’s going on. A lot of times, especially in your veggie garden, a lot of the caterpillars are going to want to munch on your plants in the evening. And then, paying attention. Are some plants performing better than others?

Then start to make hypotheses of like, why is this one doing any different?

Going back to the organic matter and your soil health. What’s going on here that’s potentially helping? What kind of landscape practices am I doing? Do I need to change something up? Should I experiment over here and try something? Because, your garden can also be a little a little laboratory as well, where you can try plants, try different practices in one spot and compare it to another and see what goes on.

Indicator Species

Mark Tancig: There’s plants that we consider indicator species. More shallow rooted species will start to wilt first. [A] common landscape plan that we think of is azaleas; they will sometimes be the ones that wilt first.

When the azaleas start wilting, the other landscape plants are probably going to be in need of some water as well.

We had been talking about whether to water plants that wilt on a hot afternoon.

That late afternoon thing you’re talking about, that’s just the heat of the day. And some of them are just like, “Okay, we’re just going to stop for now and slow down. We’ll be back in the morning.” If you notice they’re still wilted in the morning, that’s when you know there’s some problems and you definitely need the water in your yard.