If dreams of a riotously colorful cottage garden or sculptured beds of tidy flowers fill your imagination all summer long, don't put away your tools for the winter quite yet.  Fall brings weather that's just right for bringing those dreams to life. 

Cool, moist conditions in late fall are favorable for good root systems to develop before the coldest part of winter sets in. It's a great time to plant trees, shrubs, perennial flowers and bulbs that will bring beautiful blossoms year after year. Many nurseries and mail-order outlets offer great bargains on containerized plants as end-of-the-season specials. 

A "perennial" is a plant that lives for more than two years.  Some are evergreen and hold their foliage year-round.  Others die back to the ground after frost, but emerge again from hardy roots the following spring. 

Successful planting starts with preparing planting holes that are large enough to accommodate plants without crowding the roots.  Select a suitable place for the plant, a location that will accommodate its mature size and provide the right amount of sunlight.  Keep in mind, too, how it will look in full bloom next to neighboring plants.  

Remove soil from a suitably sized hole and mix it with 1/3 organic matter such as peat moss, compost, dried manure, or decomposed leaves. 
Avoid creating a “bathtub zone." That’s what happens when you put highly amended, loose soil inside a hole whose sides are made of hard, smooth clay. Once a plant’s roots reach a zone of significantly different soil, they find it hard to penetrate and can wind round and round like they do when pot-bound. 

Blend the amendments well with the native soil, and roughen the sides of the planting hole by scraping ridges with a garden fork. Soak the surrounding soil.

Add bone meal and/or a low-nitrogen fertilizer.  The phosphorus and potassium contained in low-nitrogen fertilizer help root development and disease resistance.  Don't add nitrogen now because it stimulates leaf growth, which is vulnerable to winter damage. 

Water plants so they'll slip easily from their containers.  Inspect the roots and trim off those that are broken or unhealthy-looking.  Healthy roots are bright white inside.  If roots are pot-bound - tightly compacted and circling the outside of the root ball - gently loosen them before planting. 

Position the root ball so that the plant is at the same depth as it was in its container.  Build a cone of soil underneath if necessary to raise it up to the correct level. Fill partially around the root ball with the amended soil, firm it down, and water.  Complete filling the hole and tamp it down firmly.  Water again, and keep it watered unless winter moisture falls regularly. 

After the ground has frozen later on, apply several inches of mulch to keep the ground from alternately freezing and thawing, which heaves plants out of the ground.
 
Perennials planted in fall will begin greening up in spring, at which time a balanced fertilizer containing nitrogen, phosphorus and potassium should be applied.

Many perennials bloom the following year after being planted, although some recalcitrant plants do take longer. One thing is for sure: Planting once - for years of garden beauty - is easier than planting annuals year-after-year, and with beautiful results for your garden and landscape.