How do I get rid of ants in my garden organically?
I have a set of raised beds in Phoenix and this is my first season living and planting here. I planted mainly tomatoes and zucchini and they did well until about late May when I had an infestation of tiny ants that began swarming on my zucchini. At first I thought I had end rot as I had plenty of blooms, got all of 3 zucchini and then they stopped growing. They get about 2-3 inches long, then turn yellow and die. I have tiny ants (that bite) swarming all over the zucchini plants and the beds. They pretty much left the tomatoes alone until I just pulled the zucchini plants out.
I tried organic diatomaceous earth but that's not seeming to help. How can I get rid of the ants once and for all without using a bunch of chemical pesticides?
First things first. The zucchini fruits you describe are unpollinated fruit that can not fully develop. The first flowers that appear are female and without male flowers they get a few inches long and abort. The ants will swarm these decaying fruits to extract sugars. Soon the male flowers will begin to come out and they will provide the pollen needed to develop healthy fruit.
Besides the decaying fruits the ants may be on plants due to the presence of aphids, soft scale, mealybugs or whitefly, or the presence of floral nectar. Control the insect infestation if the ants are after their honeydew. If you can find the ant colony - ringing the opening of the den with diatomaceous earth should discourage them. Pouring d-Limonene into the opening of the den will also discourage them.
I can't seem to find the colony, and the an's have seemed to just shift to a different part of the garden, I see them on the sides of the beds and some of the other plants, although not to the extent that they were on the zucchini. Should I just pull everything and try to start over? If I do that, how do I treat the entire garden for the ants without being able to find the colony?
This is the problem with insects and ants in particular. Trying to find where they live can be a problem and once you find them and destroy them another colony will take up residence. You might want to contact the Master Gardeners in Maricopa County for additional advice. 602- 827-8200 or http://extension.arizona.edu/maricopamg