R41, the plants that flower all summer are annuals. They come from warm places where they bloom all year round. We can grow them in temperate climate in summer, but yes, they will need to be bought in spring.
Everyone used to use impatiens for color in the garden. They worked great. Unfortunately, there is a fungus that is killing them. They still sellimpatiens in my area, but they really shouldn’t because they won’t survive long before the fungus gets them.
Sunpatiens are an annual hybrid that seem to hold up well, but you can’t buy a flat of them, like you could impatiens. I don’t know why not. They are more expensive than impatiens. because stores only sell them in large sizes.
Petunias are annuals that can bring summer-long color to a garden. They come in cellpacks in big box stores, so you can get them for a good price if you check for sales. Sales usually start Memorial Day weekend.
Salvia Amistad is what’s called a tender perennial. It’s a perennial in warm climates, but in temperate areas, it’s an annual.
It’s trial and error. If you plant perennials you will find that they do what they want to. It was too cold this winter? Not coming back. Too much rain? Not coming back. But one thing you’ll find that is very annoying — they don’t come back where you planted them. They come back 4 inches to the left, or 8 inches to the right. If they established good root systems, they could come back almost a foot away from where you planted them. They decide “this is warmer/dryer/sunnier here than where I was last year. I’ll send up my shoots over here.”
I live in a rich area and see women in their big brimmed hats at the local garden center buying absolutely beautiful plants that will be arranged in a beautiful garden. But I don’t have that kind of money, so I plant native, non-flashy perennials that birds, butterflies and bees like. They’re not pretty like what you see in magazines. I tried planting gorgeous plants and they could tell I am working class and said, “Fuck you.” So I use the tried and true perennials - coneflowers, black eyed Susans, day lilies, daffodils, coreopsis, butterfly bush, catmint, astilbe. I throw some annuals in for color but I just don’t have the eye for arranging things.