If you've saved and dried rose petals and fragrant flowers all summer, you're on schedule for making your own potpourri.

Most of us lack the plants, time and ambition to create potpourri, especially when an assortment of captivating fragrances is commercially available in aerosols, essential oils and bouquets of dried flowers. It's hard to surpass these commercial concoctions; one whiff and you think paradise comes in the container.

Much to the dismay of fragrance retailers, some gardeners still perpetuate a grandmother-mother-daughter heritage of making their own potpourri. While the fragrance may not approach the commercial ones, homemade potpourri is still the standard of excellence for gardeners. Start a tradition this fall by making your own potpourri.

There are many down-to-earth books on the subject. Strongly recommended are "Potpourri, Incense and Other Fragrant Concoctions" by Ann Tucker Fettner ($5); "The Scented Room" by Barbara Milo Ohrbach ($18); "Dried Flowers For All Seasons," by Betty Wiita ($19), and the "Encyclopedia of Herbs and Herbalism" by Malcolm Stuart ($35). County Cooperative Extension Service offices and the Department of Agriculture also have inexpensive booklets on dried flowers and potpourri, many for less than $1.

Potpourri may be created from moist or dry recipes, but the dry formulas are easier. Here is the basic dry recipe. You can increase or reduce the formula depending on the amount of dried flowers you have on hand:

Fill a gallon pail with dried rose petals. Separately, add six ounces of kitchen salt to a bowl. Find a very large jar (such as an earthenware crock or the largest cookie jar) and place layer after layer of rose petals in it, sprinkling the salt uniformly over each layer so all of it is used.

Atop the sandwich of rose petals and salt, sprinkle four to six handfuls of other dried flower petals. Finally, over the entire contents, add one ounce of brown sugar, one ounce of orris root, two ounces of gum benzoin, two ounces of cloves, two ounces of allspice and two ounces of powdered bay salt. Pour a jigger of brandy over it all.

Mix all materials with your hands, making sure not to bruise the petals. Slow, careful mixing will give you a perfect blend. Finally, screw on the cover and store the jar in a dark, cool closet.

Let this stand for four weeks, after which you can personalize your potpourri as grandmother did. Divide the contents of the large container into small jars, leaving an inch of air space at the top of the jar.

Accent each of the basic potpourri jars with your own recipe. Add a dash of lavender oil to one jar, geranium oil to another, musk oil or essence of amber to another. You can even add some well-dried lemon peel to one jar, nutmeg to another. If you use essential oil, two or three drops will yield a superior scent.

After three weeks, unscrew the cover and mix ingredients with your hand, then return the cover for three more weeks. After six weeks, the potpourri is fixed and ready to be used. Put the containers, covers ajar, in rooms where you want the fragrance.

Normally, potpourri will release its entire fragrance in 20 to 24 months, but it may be rejuvenated anytime by adding more to the jar, perhaps several inches of scented petals to which two drops of essential oil have been added.

Most potpourri ingredients, including essential oils and rejuvenators, are available at department stores and specialty shops.

In the outdoor garden, a host of chores are on the agenda this weekend. Here are some of the priorities:

Fertilize your lawn again. This is the third fall feeding, with one more to go two weeks from now (Oct. 17-18). Cut the lawn first, bagging the clips, then apply 10-6-4 inorganic at the rate of five pounds per 1,000 square feet. Spreader settings are the same as the last September feeding: 4 3/4 on the rotary Cyclone or Spyker, 5 1/4 on the Scott drop spreader. Soak the lawn if rain isn't due soon.

Chrysanthemums will prosper with some tender, loving care. Large flowering mums will benefit from pinching some lateral buds, but don't touch cushion mums. Using a soaker hose twice a week around mums to extend the life of the flowers.

Outdoor container and potted mums should be watered daily to extend blossom life. Indoor mums are best located away from direct sunlight; moving the pot up close to a north window (closed, of course) will suffice, but add a tablespoon or two of warm water to the pot every day. Elsewhere, water to keep the soil lightly moist. If you're buying mums for display indoors, check the plants first at the garden shop to make sure they're free of whiteflies; to check, simply jostle the tall stalks and any whiteflies will be airborne.

You sprayed blueberry plants this week for the blueberry mite, and you'll soon attack the scale (oystershell scale, euonymus scale, Putnam scale, etc.) just laid by the female. Early November is the target for killing scale eggs, gypsy moth eggs and overwintering insects, so lay in a supply of superior oil (Rockland dormant oil or Security dormant oil); other dormant oils are not "superior oil" unless the viscosity shows 65 seconds or more.

Cut peony stalks to the ground now, removing debris from the site to minimize disease problems next spring. Take advantage of the mild weather to run a pH test of the soil (depth of four to six inches). Peonies perform best when the pH is in the 6.5-6.8 range. A thimble of soil at this depth will enable the garden shop to test, otherwise you can use the instant readout instruments that read the pH immediately. If lime is needed, use ground limestone (most inexpensive) since the soil pH won't have to be raised until next April. Work a few garden shovels of composted cow manure into the soil away from the tubers, scratching it into the soil to a depth of two to three inches.

Amaryllis should be moved from cool quarters to the warmest spot in the house next week. Don't do anything to the potted amaryllis except move it to a place where temperatures are consistently above 68 degrees. Consider a shelf near the furnace, or on a closet shelf in a room with south-facing windows. Open the shades, curtains or blinds to allow sunlight into the room during the day, shutting the door to retain as much heat as possible. The amaryllis stays there for the next four weeks. After that, embark on a new care program to force the giant flowers in time for Christmas. If you don't have an amaryllis, raid the budget and buy a few tubers over the next four weeks. Plants last 20 years with minimum care, with seven-inch flowers showing from Christmas to early April.

NEXT WEEK: Caring for bedding plants you want to save for the winter. Jack Eden hosts "Over the Garden Fence" Sundays from 10 a.m. to 1 p.m. on WTOP Radio (1500AM).