September is a great time of year to plant perennial flowers. Most gardeners shy away from fall planting because they worry the plants won't survive winter. But if you plant in September, your perennials will have plenty of time to put down their roots before the cold.
Another advantage to fall planting is nurseries and garden centers are offering sales to move their stock. You can even find public gardens holding plant sales to raise money and offer some rare and unique plants. One such plant sale is happening at theHollister House Public Garden in Washington on the September 11th. Check it out. You can get inspired by their display gardens while picking up some unusual plants.
Once you get your plants home, don't delay in planting. The sooner they're in the ground, the faster they'll get established. Find the right location with proper sun or shade and well-drained soil for your new babies. Remember a garden that's shaded in September, may be in full sun in June, so plant based on the other perennials in that bed.
Plant in groups of 3, 5 or 7 for the best display. It's okay to cut off blooms or yellowing leaves. The plant is probably going dormant this time of year anyway. Take a photo, mark or draw on a map where you planted the newbies because in spring, you may forget. For perennials that might be a little tender for our climate, mulch with a 3- to 4-inch thick layer of wood chips in November to protect the roots and prevent frost heaves from unearthing the new plant. Don't be surprised if your new plants are a little slow to emerge next spring, but just for the first year.