Propagation: Planting out seedlings (mostly annual flowers), 2 by FaintlyMacabre

FaintlyMacabre wrote:
Hullo gardeners! New (this year) to seed starting and DG, unless lurking for several months counts.

I\'m posting, at last, to ask about which sorts of seedlings can be planted out before frosts are over. Finding this information is tough by searching, whether here or more widely.... I have the hazy sense that species that are frost-tolerant on the other end (when full-grown in the fall) aren\'t necessarily ready to face a late spring frost (makes sense, since THEY\'RE BABIES).

But indoor-light space is tight...and my yard is a zone 6b eastern Massachusetts wasteland....and surely some of these sprouts would love to be out there despite the \"low of 34\" forecast for a couple of nights this week. I\'ve started hardening off many of the seedlings, apart from those (heat-loving vines) that I know can\'t go till late May. But for actual planting, does anyone know about

Stocks?
Snapdragons?
Globe amaranths?
Salvia?
Impatiens?
Alyssum? (ready to experiment with some of those)
Cosmos? ( a few of those are out already)
Windowbox (annual) lobelia?

perennials also: Echinacea (I put three of them out, to see how they do) and hyssop.

Will try to include photos.