You described flea beetles. The adults eat leaves. They jump around so the damage is not as apparent as with caterpillars. Instead, the holes chewed in the leaves are smaller, but can be found throughout the plant. Their pupae live in the soil chewing on roots. The combination of attacks on the canopy and the roots severely damages the plant, leaving it vulnerable to attack by pathogens.
These insects can be eliminated using organic means. To knock down the population of adults feeding on the leaves as well as the pupae, use a pyrethrum spray and pyrethrum drench. Then use Botanigard, which is a myco-insecticide. The living fungus attacks insects, but is not interested in you or your pets.
Beneficial nematodes should be added to the soil. They will eat the pupae and eliminate any remaining pests before they mature.
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