Think Design, Not Herbicide

Weeds love the hot sun and Florida summer showers. After a few questions from friends about what I recommend for weed control, I wanted to write this piece to encourage homeowners to look away from herbicides like RoundUp and Spectracide, and others, and think about garden design. Environmental conservation is important to most people. It is a passion of mine, and one of the foundations of any of our design work at Coyle & Caron. 

What is a weed, anyway? For now we'll call a weed an unwanted plant, a trespasser. My recommendations are about how to manage weeds. If you can pursue Florida-Friendly gardening tactics, you will create conditions where the plants will outcompete the weeds and you'll have a garden full of color and rich textures. This means using attractive - and useful - groundcovers and plants. This is a wonderful PDF document about plant selection and design for Florida yards, with example planting plans.

If you are reading this and thinking, I just want to get my weeds under control, I don’t want to redesign my landscape, I can understand that! So, let me get a few thoughts about herbicides out of the way. 

Herbicides

Some will argue that herbicides are safe, and have been proven so, otherwise they wouldn’t be able to purchase them. The active chemical, glyphosate, in most of them is meant to adhere to soil and not run off into our groundwaters. However, there are many active and non-active ingredients in these herbicides that do run off, and many have been proven harmful. If you absolutely must use an herbicide, please try not to use it before it rains, even if the label says “rain-safe.”

The Floridan Aquifer extends 100,000 square miles past Florida into Georgia and even South Carolina. It is the source of about 90% of our drinking water, and it feeds our springs, lakes and rivers. Throughout Central Florida, the Surficial Aquifer System is present near land surface. Any run off from gardening activities will eventually make it into our water supply; whether that is fertilizer or herbicides, rain filters it back to our groundwater system through the ground (soil), lakes/canals/retention ponds, and structures such as storm drains.  

Although our drinking water is naturally filtered as it makes its way through the ground into the aquifer, Florida wildlife that accesses water closer to the surface is still impacted by these unfiltered chemicals. The fish, otters, gators and birds that live in our waters do not have the luxury of getting their home filtered. For example, if a lakefront neighborhood’s fertilizers upset the natural balance of that lake, a resulting algae bloom has a ripple effect for the native plants that the wildlife of this lake depend upon.

What about homemade herbicides? Common ones that are recommended are vinegar, Dawn detergent, salt and boiling water recipes. Dawn is relatively harmless, but in most recipes it functions to get the vinegar or salt to adhere to the weeds. Boiling water is safe and effective to cook a stubborn weed or two, down to the roots, but for all the energy wasted and time to stand over them with a kettle, you may as well just pull them. Vinegar has mixed results and burns the leaves of the weeds, not the roots. I do not recommend salt for any reason. The ancient Romans salted the earth of their enemies, because once it gets into the ground, nothing will ever grow again, at least for a very, very long time. And it is a heavy mineral, that will migrate deep into your yard and into our water tables. Our freshwater wildlife cannot survive in saline waters – even the smallest increase in salinity is harmful.

For troublesome garden areas, the only choice is old fashioned weed pulling, followed by control strategies that include weed cloth, mulch and planting desirable plants. 

If all else fails, you could always learn to eat your weeds.

Preparation Under Hardscapes

For patios and walkways, good preparation is key. Weed cloth underneath your paving surfaces will prevent weeds from re-growing from below. It will not prevent weeds from seeding in from above.

Layered Planted Areas

The best strategy for weed control in gardens is shade and/or planting weed prone areas with Florida friendly groundcover and plants that will crowd out weeds. I wrote an earlier blog about how to construct a multi-layered pollinator garden, and you can take the same concept and apply it to most areas of your yard, even if you aren’t using plants that attract pollinators. 

Constructing areas of interest around your home is so much more beautiful than a bare wall and grass edging. Done correctly, you can reduce your lawn maintenance, improve soil fertility, increase water recharge and local cooling, and reduce the need for adding commercial fertilizer. You may even be able to reduce your energy bill with layered plantings that insulate your home from direct sun. Consider using dense, compact-growing plants to edge walkways, and small trees and medium sized plants for a variety of height and interest. 

Groundcovers 

These groundcovers do well in zone 9b, Central Florida, and they can be used creatively to break up space that was once a lawn, or in space around walkways, and for edgings:

  • Perennial Peanut
  • Holly Fern
  • Sunshine mimosa or Powderpuff (pollinator)
  • Confederate or Asiatic Jasmine
  • Coontie (only larval food for atala butterfly)
  • Sweet Potato Vine
  • Creeping Juniper
  • Blue Daze