I've never spent a lot of money on flowers for our yards. There has always been someone in the family that was willing to share seeds or small plants. This past week my mom dug up her Blue Dawn (a special kind of morning glory that blooms for a long time) and shared a bucket full of roots. I planted them along my cyclone fence for privacy. We had planned on purchasing privacy slats but they are so expensive that we decided to plant morning glories instead. I also had an asparagus fern that had babies coming up in random plances so I transplnated them along the fence, too. Receiving free vines saved us over $100. If you don't have any flower lovers in your family then you may find free plants through FREECYCLE. I periodically see free seeds and plants offered.
I think a frugal choice for plants would be those that re-seed themselves. I've never liked spending money on flowers that only produce for one season. Cosmos, Coreopsis, Geraniums, Mums, Poppies.. there are a host of flowers that will give years of enjoyment without having to buy them every year. It's fun to share seeds with others, too. I was walking in the neighborhood one day and fell in love with some Aster plants. The next time I walked by the owner was outside and I commented how much I loved her flowers. She immediately offered me some seeds. That was so nice of her. I have found that flower lovers are generally nice people. :-)
I'm also fond of plants that don't require a lot of water.. especially since we are on a tight budget. I have quite a few plants that fit that descriptions such as Iris, Surprise Lilies, Geraniums, Dusty Miller, Tiger Lilies, Camellias and a small pink clover plant.
I want to improve my soil so that it will hold water longer. I'm using a lot of water now that the summer is heat is here. I plan on using my homemade compost in the flower beds too and not just the vegetable garden. I have rinse water running from the washing machine to water flowers (not veggies) alongside the house. I'm still saving the rinse water from the dishes and the beginning water before it turns hot. I throw those on the flowers, too.
My yard gives me so much enjoyment. I love going out after dinner and working until dusk. It's great exercise, too.
How do you save money in your yard? Our vegetable garden is doing so well that I'm tempted to tear out the lawn and flowers and make it all veggies and fruit. I keep wondering why I am paying out water for decorations instead of food. But... I do enjoy the flowers.. so .. for now they are safe. :-)