Can I Still Start Seeds?

We live in Baltimore City, MD. Our hardiness zone is 7. Would you kindly let me know if it is too late to plant seeds? Can I start seeds in peat pots? I put it off, and I'm worried it's too late for this year. I'd like to start a few dark red Crepe Myrtles, some ornamental grasses, tomatoes, butterfly bushes, fire thorns, cucumbers and some hot red peppers. We have potting soil, perlite and a warm place. Please let me know, and any other information as I'm pretty darn new at this! Am keeping my fingers crossed! Thank you all.

Hardiness Zone: 7a

By Jane from Baltimore, MD