posted 6 years ago
I agree. Save the seeds of the plants you liked! Aphids or their eggs are always out there, but they only proliferate and case trouble sometimes. Eliot Coleman says they especially cause trouble when the plants have too much nitrogen, or underwatering because watering can flush out nitrogen from the soil. In my experience, that does seem to be true, but other times there's a little aphid epidemic when i don't think there's too much nitrogen or insufficient watering. Also, it's not a bad thing to have those few aphids around all the time: hopefully their predators' populations also stay steady, and ready to jump in if the aphids proliferate on one type of plant or another. I sometimes squish aphids, and in many cases, one type of plant will have aphids when it is small and tender, and then I squish them, and they reduce a lot as the plant grows bigger.
Works at a residential alternative high school in the Himalayas SECMOL.org . "Back home" is Cape Cod, E Coast USA.