Is it a conspiracy, ants and aphids working together to destroy all that you have worked for in your garden? You’ll actually find a very diverse and intricate ecosystem in your garden.
For instance, last summer I noticed aphids on my watermelon and cucumber plants. Something strange was happening. Since the watermelon was the only plant hit really hard by aphids, a few questions cropped up. The cucumbers sported only a few aphids, and no harm done. What? Why?? (I said a few didn’t I?)
The watermelon was decimated. Aphids travel by air, since some of them form wings through hormonal transformation when they become overcrowded on leaves. They fly away to create a new colony of clones. My watermelon plant grew about 2 meters (~6.6 feet) from the cucumbers. An aphid would not find it difficult to get from one to the other. So why was the cucumber spared from a disastrous level of aphid infestation?
It turns out that aphids aren’t the bad guys. A few won’t hurt anything. They are herded and protected by ants. Ants leave a scent as they walk that creates the trail they all follow. Evolutionarily, that’s smart. Here’s the freebie: aphids become docile around that substance, making them stick around in larger numbers, sucking your plants dry.
The aphids get mob protection and the ants get paid in food – they get to eat the sugary substance secreted by the aphids (yes, off of the aphid butts). This is where I tell you the good news. In the absence of ants an aphid population will thin itself out naturally, right? It must be that if we keep ants away from aphids, the aphid populations can’t grow to plant-killing sizes, and our crops won’t suffer. So protecting your aphids from ants will protect your plants. And they said I couldn’t rhyme anything with the word ‘plants’!
Physical barriers like the steep and smooth side of the planters I’m using will deter ants, but you’ll have to wipe them clean almost every day. Keep vines up off of the ground and keep your plants contained, or use diatomaceous earth to create a barrier. Diatomaceous earth is chalk, made from marine diatoms (the glass skeletons of algae!), turned into a powder. It scratches the exoskeleton of ants and other bugs causing them to dehydrate and die. With ants gone you may even find ladybugs or assassin bugs swooping in to save the day!
What has worked for me is to keep watch, and diligently clean the sides of the bucket so ants never get a chance to climb.
Do you know of a friendlier alternative to diatomaceous earth? Or shall we just watch the world dry up?