Raising Ladybugs: Why Buying Them Rarely Works

Q: How to raise ladybugs in quantity? I saw huge masses in a water tower.

I don't know how to raise them, but buying is ineffective. Most sold are harvested from California mountains. Summer releases stay local but don't eat (living on fat). Spring releases disperse widely. Neither reliably controls aphids.

Better: Attract natives with dill, bronze fennel, Queen Anne's lace, yarrow, carrots (let flower). Wheast™ spray also attracts/feeds them.