Hello Amanda,
You do still probably have about 3 months of frost-free nights, so you could still purchase non-hardy bedding for your hanging baskets. If they are watered and fed well they will soon catch up with other earlier planted examples.
In this time of drought you could consider a hanging basket filled with succulent plants (some will withstand temperatures down to 0C) that store water in their leaves and stems, just make sure the compost is very free draining with added grit.
Not hardy of course, but you might still be able to purchase some cherry tomato plants, I have always found they do well in hanging baskets.
If positioned outside a kitchen window, I think its great to grow 4 or 5 different herbs in a hanging basket.
Other hardy plants you could consider for hanging baskets:
Lysimachia nummularia ‘Aurea’ (Golden Creeping Jenny)
All varieties of
Aubrieta (although they won’t flower now until next spring)
Campanula species and varieties that trail.
Regards, George.