IN THE GARDEN PANSIES, VIOLAS AND VIOLETS PERFECT FOR FALL.

Byline: JOSHUA SISKIN

When it comes to fall gardens, the triumvirate of pansy, viola and violet cannot be ignored. These closely related plants are designed to bring grace, whimsy and joy into the garden. At your first fall sighting of these sprightly charmers, a smile is guaranteed to appear on your face.

The soft velvet blooms of pansies belie their toughness. Pansies will survive a frost and - where spent flowers are regularly removed - may bloom through the Fourth of July. It is only hot weather that brings about their undoing. In truth, pansies are perennials and, in climates cooler than our own, have been known to survive for several years or more.

The flowers of viola, also known as Johnny-jump-up, are about one-third to one-half the size of pansy blooms. Hybridization of pansy and viola has resulted in many new eye-catching configurations, with facelike and whiskered markings on petals of blue, violet-black and every shade of yellow.

The Viola 'Sorbet' series includes enticingly named varieties such as 'Blackberry Cream,' 'Lemon Chiffon,' 'Blue Heaven,' 'Sunny Royale' and 'Yesterday, Today and Tomorrow,' whose flowers change from white to blue after they open. Viola self sows in the garden and, from one crop to the next, has been known to stay in bloom continuously for 12 months or longer. Noteworthy new pansy cultivars include 'Panola Violet Picotee' and 'Panola Orange Imperial.'

In fall and winter plantings, the best exposure for pansies and violas is full sun while an allotment of no more than partial sun is required for a spring planting. Pansy seeds may be sown throughout the year.

Pansies and violas should be planted in well-amended, quickly draining soil. They are susceptible to fungus diseases and, were they to die not long after planting, it would be best not to replace them with more pansies. The fungus that decimates a first crop of flowers will remain in the soil for some time and would be equally unkind to a second crop of the same flower type.

Replace fungus-killed pansies with dianthus, a long-flowering species, also suitable for fall planting, that is more or less resistant to pansy plagues.

In any case, you are bound to have more success by planting pansies and violas now than in another month or two. Pansies planted now will put on good root growth and establish themselves for a long tenure in your garden.

Viola hederacea is a perennial ground cover with delicate leaves and gemlike purple and white flowers. It blooms most of the year where it is protected from hot sun.

TIP OF THE WEEK: Cut back on watering of lawns and beds. During the fall, lawns should not need watering more than three days a week, and established perennial beds will be fine with one or two weekly soakings. Newly planted flower and vegetable gardens should be watered daily for the first two weeks and every two or three days after that.