Gardening Again After a Flood

2025 has been a banner year for floods, and their destruction has been almost unfathomable. Here in the U.S., we were shocked and saddened by the Central Texas floods and their devastating death toll, but ruinous flooding has been happening all over the world. Large swaths of Africa have been severely affected, and Brazil has had its worst-ever floods. Pakistan, India, and China are no strangers to flooding, but even they have had bigger, stronger, and more frequent floods.  While dealing with such natural disasters is a nearly impossible task, dealing with flooding in your garden is very manageable. 

Where to begin: 

The only actions that can be taken while the water is still present are diversion or pumping it out, both of which can be impractical at best in an active flood situation. It is best to stay out of floodwaters; they can be full of creatures as well as organic (think sewage) and non-organic contaminants. Fire Ants, for instance, form rafts of many thousands of individuals to escape floodwaters, and you do not want to bump into one of those! Watch them in action here.

Once the water is gone: 

If there is trash, tree, or plant debris, you will want to get that out of your space. If you have flood-
deposited soil, you’ll have to decide if it should be removed. Although as little as one inch of silt can kill a lawn and only a few inches can kill a tree, removing the silt may not be the best idea. Adding and removing soil can be very hard work, is quite costly, puts you in danger of handling contaminants, and is damaging to the soil (more on that below). It might be best to simply scrape residue away from some of the bigger plants and start all over.

Assess your soil: 

Whatever you do, do not work wet soil – it can cause serious damage to the soil structure. Wet soil can easily become compressed, which can lead to compaction and drainage issues when it dries. Wait at least several days to weeks before digging, and if you plan to rototill, the recommended wait time is 90 days. You will want to determine how your soil biology held up to all the water. Soil microbes are an essential part of a healthy soil, and they need oxygen. If the soil is submerged overly long, water displaces the oxygen in it, and beneficial microorganisms can suffocate and die. Anaerobic microbes, which do not need oxygen, may take their place. A foul-smelling soil is an excellent indicator that this has happened and that the soil needs to be brought back to a healthy balance before any planting is done.

Plant viability:

 How your plants are affected by flooding depends on many factors: the length of time they were
underwater, what kind of plants they are, where they are in their lifecycle, the time of year it is, and the type of water that flooded. Warm-weather flooding will affect plants more than flooding that occurs when plants are dormant in chilly weather. Salt water will be much more damaging to most plants than will fresh water. Determining the condition of your plants can be tricky, as symptoms can take weeks and even years to appear. Vegetables and flowering annuals will show symptoms before trees and shrubs. Damage caused by flooding mirrors common disease problems, so the root cause is often unclear. If you have questions, contact your local Cooperative Extension to get expert information on your specific area. Here is a link to find the one nearest to you.

Vegetable gardens:

 First off, any produce that has gone through a flood should not be eaten. This is an EPA
recommendation, and it makes good sense. With all the unknowns in floodwater, it is the only way to be sure you are not ingesting contaminants. With fruiting vegetables, any fruit on them during the flood needs to be discarded, but whatever grows later should be fine. If you wish to err on the side of caution, wash those fruits thoroughly and plant a non-edible crop for a season.

What to do before replanting: 

As with all planting, start with your soil. A soil test is highly recommended after flooding. Water is notoriously good at leaching nutrients from soil, so even a minor water issue can affect what you’re planting in. If a soil test is not for you, you should still amend your soil and lightly fertilize (no heavy fertilizer while the plant struggles to come back). You can’t go wrong with the following: Apply BioAct SD to chew through organic material; use products like ROOT, EM-1, SCD BioAg or Mikrobs to return to a healthy microbial balance; add Earthworm Castings and, when the new plants are in, fertilize with Arber Soil and Root Food or any of our other excellent fertilizers; see our full range here.

Bear in mind that fungal diseases are common after floods, and they are best controlled by applying proactively; so, plan to treat as soon as you can. Cease would be a top-notch choice for this job, or choose another of our fine products on our Fungicides page.

Submitted by Pam 

Controlling Ants Outdoors

There are two ways to approach controlling ants:

• Decide to do nothing. Ants are critical detrivores in their eco-system. They help break down dead and dying plant material, eat soft-bodied pest insects and aerate the soil. (Click here for more information on the importance of ants) So if they are not bothering humans or your favorite 4-legger, it may be best to leave the ants alone.

• Control them efficiently and safely by understanding the behavior and social structure of the species of ant you are dealing with. 

Here are some general rules for controlling a colony of ants: 

Take Out the Queen and Kill the Colony. 

Entomopathogenic* beneficial nematodes can be used to parasitize and kill the queen. The species, Heterorhabditis bacteriaphora, can be applied to the ant nest and they will seek out and kill the queen through the process of parasitizing and injecting their bacteria into the queen. Nematodes must be applied directly to the ant mounds so that they can reach the queen. 

Sharing Doesn’t Necessarily Mean Caring.
Because the ant social structure means that food will be brought into the nest and shared, we can take advantage of this behavior to achieve control. 

Many species of ants are attracted to sugar, so the bait traps that use a sweet, syrupy liquid laced with borax or boric acid are very effective both for indoor and outdoor control. For best results, it is important to place these traps along the trails that the ants are travelling. The worker ants will take bits of the sugary liquid back to the nest to share and expand the deadly effects of the borax or boric acid. The content of these traps is not enough to cause harm to your 4-leggers but it is best to keep the traps out of their reach anyway. 

Much like bees and humans, ants live complex lives. They are ubiquitous to the planet and some do good while others cause harm. Although some of their behaviors are consistent from one species to another, there are unique behaviors by many ants. This can make controlling for them a complicated matter. However, proper identification of the species will help save time and money in treating them. 

Weird Facts About Ants:

Fire Ants can have multiple queens making control more difficult and the use of beneficial nematodes less successful. Organic controls include drenching their mounds with orange oil based Orange Guard Fire Ant Control and surrounding the mounds with Diatomaceous Earth. As they attempt to escape the Orange Guard, they pick up the DE and that desiccates their exoskeletons.

Harvester Ants build their nests upside down – with larger chambers closer to the surface and small and smaller chambers deeper in the nest. They are stinging red ants and are often confused with fire ants. However, their behavior is not like fire ants and their sting is not as severe. They can be controlled with nematodes and bait traps. 

Leafcutter Ants – This is a group of 47 ant species that form large and complex societies. Their social structures are second only to humans. Their nests can span and radiate out to 6,400 square ft. Large nests can contain 8,000,000 individual ants. You can control them by using nematodes and DE at the mounds. You can also spray their target plants with a botanical oil. Or try pasting Stiky Stuff around the base or trunk of the plants that they are harvesting leaves from. 

*Entomopathogenic nematodes – A group of nematodes that cause death to pest insects. The word entomopathogenic refers to insect and pathogen (causing disease). These nematodes live as a parasite inside the host insect and they infect their host with a bacterial disease. Once the insect is infected, the nematodes reproduce multiple generations.  

- Contributed by Deb at ARBICO Organics