Ants on plants and in soil

I have a Meyer Lemon planted in a large pot. It's been enjoying the outdoors for several months, but now I have to prepare to move it indoors for the winter (I'm in Zone 7a, in eastern Tennessee). However, it now has ants crawling up and down the truck and around on top of the soil and on the rim of the pot. How can I safely rid the plant and soil of the ants before bringing it indoors? Does anyone know? Thanks.

You can try simple solutions like flooding the soil. Can you set it somewhere and turn the hose on for an hour or more? That might make them leave. Or even better plunge the whole pot into a deep tub of water, deeper than the soil. Keep it there for long enough for the ants to leave.

For ants that you can see I would spray with something like insecticidal soap.

If the plant is ready for repotting you could knock off all the loose soil then soak the plant in the tub of water to loosen the rest of the soil, or at least chase out the ants. .

I would use Grant's ant bait, or something that works as well (not Raid, Hot Shot, or the other useless brands). Grant's baits are gelatin inside plastic trays. The ants chew off a lump and carry it back to the nest where everyone eats it and the colony dies. Sad for the colony, but but unlike sprays and so on, no other insects or critters are affected.

If the ants are nesting in your pot, I fear even soaking it will only be a temporary solution. They are amazingly resilient.

Another question might be WHY the ants are all over the tree. I'd check it very closely for mealy bugs, root mealy bugs, aphids, and other insects that produce "honeydew" since an ant infestation sometimes means they are harvesting honeydew from these insects.

Ants are the bane of my plant existence. On any given day, they are in at least 15-20 of my pots, especially the ones in more sun... but not always.

Sometimes they can be evicted by submerging pots in a tub of water. Sometimes, even after 24 hours, there are still ants walking around under the water. My plants don't have pests, and the ants don't seem to directly affect plants, but their nesting ruins the soil structure in the pots, causing compaction and hydrophobic areas. Both of those can cause problems.

If the root ball will slide out of the pot w/o falling apart, that seems to be the best/quickest/easiest way to evict them. Remove, water gently but thoroughly, observe. In an hour or 2, they are *usually* all gone, no longer a suitable atmosphere for their nefarious nesting.

Repotting is always a good option, though not always from the POV of your wallet.

For years, I've been trying to determine why they choose a particular pot over another. What's the pattern? Pots can be invaded sitting on the ground, on a porch, in total shade, in full sun, hanging from anything... Generally, they don't invade a very moist pot. With no way to measure, the following is just a hunch, but they may prefer higher PH soil. (Sometimes I mix my own in a baby pool and don't always use the same stuff, so never have the exact same results.) Although there's no way to know which is the chicken or the egg. Did the PH attract them and cause a plant to look borderline chlorotic, or did that happen after the ants came in? IDK... (frown!!) I don't usually notice ants in a pot unless I water or move the pot. Then they swarm out if they are in there, and of course, it's obvious then - and their trail is also then obvious. Usually than easy to track the ant-highway. Every time, if I follow these particular kind of pot-ants to wherever it is they are going, it always leads to a tree or stump.

My thanks to all the kind responders for all their suggestions. My tree does not appear to have any other pest (no aphids, for example, nor mealy bugs above or below soil line) or disease -- just the ants. Thanks again.

Well, if they do not leave when you flood it, then you may need to add something to the water. You might start with some dish soap (1 tablespoon per gallon) or insecticidal soap, or a surfactant, also called a wetting agent, sold as a spray additive, or to help the water soak into the soil. Names like Water In and Water Wet are this sort of product.

After these pretty innocuous things you would have to step up to a real pesticide.

I just got rid of most ants off my hibiscus pot with a simple trick. Mix in some sugar water yeast flour and lots of baking powder/soda. Make small thumb sized balls and place it inside the pot. The ants will all crowd around it and eat it and even perhaps take it to their den for the queen.

When they eat it, the yeast and soda expand their insides and kill them.

I put in the night before and within just a few hours the balls were covered completely with ants. Next morning there were none around but I still replaced the balls with new ones so the few left out would also be taken care of. The best part is, they left the flowers alone when food was available on the ground.

You can also use borax or chemical pesticides in the dough but I don't use chemicals around my plants.

In that small amount the baking soda (sodium bicarbonate) is not much of an issue. Used in larger amounts it can raise the pH of the soil.
The borax might be a different problem. While boron is a necessary plant nutrient, they need it in VERY SMALL doses. Even a little bit too much can be toxic.

Be careful also of dihydrogen monoxide. Nasty chemical!
http://www.dhmo.org/facts.html