KNOW YOUR VINE I've already shown you one of the most important things you can do to ensure beautiful clematis — pruning the right way for your type. Here are six more steps.

START WITH THE SOIL It is true that clematis prefer slightly alkaline soil. If a soil test tells you that yours is on the acid side, your vines will benefit from some agricultural lime. But if it's already alkaline, don't add lime—you can overdo it. A pH of 7 to 7.5 is just right.

MULCHING MATTERS "Head in the sun, feet in the shade" is old clematis advice. However, a 4-inch layer of mulch keeps the roots cool and moist just as well as shade does. To prevent stem rot, keep the mulch about 8 inches from the stems.

MAKING THE CUT The best place to prune a stem is just above two strong buds. The illustration at left shows how you can spot them — where two leaves were growing the previous year. These buds will quickly develop into new vines. Don't worry about making angled cuts —it's not necessary.

RECOGNIZE DISEASE QUICKLY Clematis wilt is easy to spot: A portion of your vine wilts quickly, often just as the plant starts to bloom. Wilt is caused by a fungus that enters the stem, usually just above the soil line. There is no cure other than to cut the entire stem to the ground and dispose of it in the trash. Do this as soon as you notice the wilt. That'll prevent spores from moving to other stems. Systemic fungicides can help prevent wilt from spreading to healthy stems. Apply benomyi or carbendazim to vines immediately after you remove infected por­tions. Read the package label for specific appli­cation information. The rest of the plant usu­ally survives, providing there are enough other healthy stems. That's another reason to plant clematis deeply: If a stem becomes infected and has to be removed, more will come from the base to replace it
Cultivars that have proven resistant to wilt include The President', 'Ville de Lyon', 'Nelly Moser', 'Betty Corning' and 'Jackmanii'.

SERVE A BALANCED DIET Clematis like to be well fed, but not overfed. I feed my clematis once a year right after pruning with an all-pur­pose, granulated fertilizer, such as a 10-10-10.

CHOOSE THE RIGHT TRELLIS Clematis climb by twisting petioles, or leaf stems. The vine itself does not twine. So, if your structure is too large, the leaf can't wrap around it. Anything over 3/4 inch in diameter is too large for a leaf to grasp. Nylon fishing line is a great way to get a clematis to climb a light pole or arbor post. See the small knot in the photo at right? Tie one of those every foot or so to keep the vine from sliding.