As the tomatoes start to dwindle after the best season in years, it's not time to quit gardening yet. In fact, September is one of the most important months for the vegetable garden.

As the heat of summer dissipates, it's time to get cool-weather crops planted. They can last well into fall and some will even stay around until next spring.

Lettuce is the first choice in my garden. Seeds planted in good soil, amended with compost, will reap benefits for months. Prepare the bed with organic matter such as compost or well-aged animal manure. Sprinkle fresh seed onto the newly turned soil and lightly rake it in. Soak the new bed with water and don't let it dry out until the lettuce germinates.

No matter how hard I try to space the small seed, the seedlings always need to be thinned. Luckily, those tender seedlings are heaven in a salad. I don't plant in rows; I just scatter the seed to make a carpet of greens that thrive in the cool fall weather.

Leaf lettuce and butterhead types are quick growing -- I like the old standby 'Black Seeded Simpson' and its cousin, 'Simpson Elite.' But there are other interesting varieties offering a cornucopia of shapes and colors.

Sometimes, my choices are determined by what seed I can find, and if I'm lucky enough to stumble onto plants at a nursery, I'll plant them for a jump start on the season. 'Amish Deer Tongue' is tender and I guess looks like a deer tongue. It's one of my favorites. 'Flame' and 'Red Sails' add wonderful texture and color to the garden.

Another fun thing to do is buy a packet of mixed lettuce seed. You'll end up with a rainbow of colors and flavors.

Lettuce is a great plant for containers and not just for eating. Red, spotted and curled leaves are beautiful in pots alongside flowers in the garden. One advantage of containers is they can be moved to a protected area as temperatures drop. A sun porch would offer enough light and warmth to keep the plants thriving until January.

Leaf lettuce is amazingly hardy, withstanding freezing temperatures. Every year in October, I break out the floating row covers to keep the plants growing into winter. They are inexpensive lightweight fabric that protects lettuce and other crops from very cold temperatures. Last year, I picked some 'Black Seeded Simpson' on Christmas Eve to include in our family's Feast of Seven Fishes.

Floating row covers can be used year after year, lasting three years or more if you treat them gently. This year, I'm going to cut some half-inch PVC pipe into 3-foot lengths and form small hoops to support the row covers. All that snow last season crushed some of the greens, so putting up hoops should guarantee we won't have deep snow this year.

There are other greens and vegetables that will enjoy a fall sowing, such as spinach. It's a hard crop to grow in Western Pennsylvania when planted in spring. It just gets too warm too quick and the plants go to seed, called bolting. Once this happens, the leaves become bitter. The same is true with most greens, including lettuce.

Spinach planted now is treated the same way as lettuce and other greens. Overwintered spinach will enjoy the cool March/April weather and produce a bumper crop before things get hot.

Other greens to plant include arugula, cress, mustard, corn mache, collards and kale. They all enjoy the temperatures of fall and will continue well into winter.

This is also a great time to prepare any fallow beds for spring. Piling on good organic matter then mulching with straw will hold the good stuff in place. It also provides a bed that can be planted as soon as possible early in the season regardless of torrential spring rains.

If you're not able to bring wheelbarrow-loads of compost into the garden, consider planting a "green manure" like winter rye. Once the bed is empty, winter rye seed is sown. It will sprout into late October and will stay in place until spring when it will take off. Before planting, this cover crop is dug in and acts as organic matter to improve the soil. Cover crops also prevent winter erosion of your good garden soil and attract beneficial insects.

It might seem tempting to hang up the trowel, but fall is a great time to plant and get ready for next year's garden.

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