Get an organic or food-safe insecticide, or if you're the pascifist type you could try a diversion... ants seek sugars, so maybe you could stash something sweet to try and lure them away from your crop? Personally, I use Sevindust with great results. Even though many people advise against it, it is said to be safe for fruits/veggies as long as you stop using it a week or 2 before harvest... though I'd say it's a little different with buds, I stop just 1 week before harvest and if it doesn't rain during that time I will rinse the buds thoroughly, then harvest once I know I've removed the insecticides/pesticides. This is just a method that hasworked well for me, if asked for advice though, I would recommend neem oil or something that couldn't harm you if misused (I'm not sure the effects neem oil would have on ants but it is relatively cheap, won't hurt your plants and will make your garden undesirable to most bugs.) Also, are you sure that ants are the problem? Cannabis is loved by many pests in the great outdoors (as well as indoors if you keep a sloppy grow room.) Either way, I hope I helped or sparked an idea in some way, I hate bug problems!! Good luck, good growing! Go ahead and start a couple more germinating or cut a couple more clones, you don't want to lose your whole crop after you've already put work into it.