Updated: October 6, 2009, 5:43 pm

Think Garden Season's Over? Not So Fast!

By Anne Halpin

Japanese anemone is a late-blooming perennial and can be planted in the fall. Images courtesy of Google Images

Southampton - The end of summer doesn't have to mean the end of your garden. There's still plenty of color in the garden from summer annuals, and from late-blooming perennials like Japanese anemone, asters and mums, and the lesser known toad lily (Tricyrtis). Ornamental grasses are in their full glory, with their plumy or fan-shaped seedheads waving in the breeze. Soon we'll be looking at the blazing colors of fall foliage.

Fall is a great time to plant daffodils.

But fall is a great time for planting, too, especially here on the East End. Why plant now? The weather is more congenial than in spring or summer. Spring weather is usually cold and rainy, and summer's heat and humidity are tough on new plants. But in autumn we are generally blessed with temperate days and cool nights, with lower humidity. Plants have time to settle into the garden and send out new roots before the ground freezes. While they're acclimating themselves and adapting to life in your garden, they don't have to contend with blazing sun and the intense humidity that can foster disease organisms. And the soil doesn't dry out as quickly in autumn as it does in summer.

You probably already know that fall is the time to plant spring-blooming bulbs like daffodils and tulips. They need winter cold in order to bloom next spring. You can plant them any time before the ground starts to freeze, but October is prime time. I wouldn't plant before late September, though. If you plant too early the bulbs will start to grow now, and they'll be damaged when winter hits. When you buy bulbs at a local nursery or order them by mail, they will come with instructions on how deep to plant them. Follow those guidelines if you want your bulbs to bloom for more than one year.

Using a bulb planter or trowel will ensure that holes are the correct depth.

Use a trowel or bulb planter to dig the holes to the right depth. If you're planting a whole bed of bulbs, you can excavate the planting area to the right depth and set out all the bulbs, then cover them all at once instead of digging individual holes. Sprinkle some rock phosphate in the bottom of the hole or trench before setting in the bulbs.

Fall is also a great time to plant perennials, roses, and trees and shrubs. You can order by mail if you're looking for particular varieties, or want a greater choice, or you can shop locally. Local nurseries often have deals in fall as they want to sell off their stock before closing for the winter. If you buy perennials for fall planting, they won't be in bloom anymore, and the plants may look a bit scraggly, but as long as you don't see signs of disease it's a good bet they'll be fine next year.

Trees and shrubs, both deciduous (the kind that lose their leaves in winter) or evergreen, are good candidates for fall planting. If you've been longing for another hydrangea, or need more of those Leyland cypresses to screen your property boundary, or want to try a new shrub rose, now's a good time to plant.

And here's another tip: if you like pansies for their bright colors in early spring, plant them in fall. They'll bloom until the weather really turns freezing cold, and they'll come back and bloom again in early spring. You'll have welcome color in your garden next April without having to brave the spring chill to go out and plant.

If you like pansies for their bright colors in early spring, plant them in fall - they will bloom.

Just Don't Forget To Water!
Whatever you put into your garden in fall, don't forget to water the newbies. Bulbs need water only when the soil is very dry, since they'll be going into dormancy anyway. But newly planted perennials, roses, trees and shrubs need to send out new roots to nourish them, and they need water.

Also, bear in mind that when the ground freezes in winter, plant roots can't draw moisture from the soil. This is especially critical for evergreens. Cold winter winds draw moisture from the leaves that the roots cannot replace until spring. When your evergreens turn brown in winter, that's winterburn, caused by the leaves drying out.

If fall is dry, it's really important to water your trees and shrubs—especially the evergreens—deeply when the weather turns cold, as the ground starts to freeze.

So fall is a great time to plant. It's the best weather of the year here, as far as I'm concerned. So get out your shovel and trowel and get busy. And enjoy the rewards next year!

Anne Halpin is a writer, editor and professional gardener, and the author of 17 garden, home and nature books. She lives in Hampton Bays.