This summer was very hot and dry and I noticed that even
my well-established clematis had smaller and fewer flowers this year. Why does this happen?
The symptoms you describe are typical of drought stress. Deep planting and
heavy mulching are good preventatives. A thorough, deep watering once a week is far better than frequent sprinkling.
If you live in a drought-ridden area, do try hydrogel (see Odds Et Ends)-it can be introduced around established plantings by carefully making holes
about 6" deep and 12" apart and stuffing them with the moistened product. Remember that the feeder roots of established plants will not be right next
to the crown but rather a distance away.
Hydrogel is a
polymer that works by absorbing water like a sponge and releasing this
water over a prolonged period of time when the surrounding soil dries
out. Hydrogel is available under a variety of names:
Soil-Moist, Terrasorb, etc. The trick is to soak it in warm water
prior to use (even though the instructions tell you to use it as is and
then water). Believe us, pre-soaking will save you a lot of
headaches. Its effect lasts about three years in the soil, by which
time your plant should be well established. If you want, you can
replenish it. Hydrogel can be used in containers as well, but do
bear in mind that a little goes a long way and you'll need to adjust your
watering habits accordingly.
2. After a bad storm I noticed that one of my Henryi's stems was cracked near the base. What,
if anything, should I do about it?
Cracked stems are common and not necessarily fatal. If you want to rein-force it, we have used electrical tape successfully. In general, however, unless it's a bad break, you don't need to do anything. A good drenching
with Benomyl would help ward off any possible problems with wilt.
3. No matter how much I water my Ville de Lyon loses all its lower leaves by mid-summer but the top
part is fine. What can I do about this?
You're not doing anything wrong. It is normal for clematis to shed their lower leaves as the season progresses. Ville de Lyon is one of the worst offenders. The best way to deal with this problem is by underplanting with a perennial-veronicas, phlox and asters work well or you can use any plant that is shallow-rooted and non-invasive.
4. I just moved into a new house and there are several mature unnamed clematis in
the garden. How should I prune them?
Don't prune for one season -just remove any dead bits and observe the clematis carefully to determine when they flower. This will indicate the appropriate pruning procedure for the following year. If they flower early on old wood -
i.e.. the previous year's growth - they should be pruned after flowering, and then only to tidy up. If they flower in late spring and then again in late summer/fall, they should be pruned lightly in late winter/early spring depending on your location. If they flower in late June
early July, cut them back hard in late winter/early spring.
5. When is the best time to move a clematis from one spot to another and how should I do it?
Ideally a clematis is best moved in early spring as soon as the soil is workable. If possible prep the new hole the previous fall. It should be substantially wider than the root ball you plan to dig up. Fill it with a good rich soil and a handful each of 5-10-10, lime, and
superphosphate. Cut the top growth back to 3'-4' as clematis stems are so brittle early in the year that if they're any longer they'll snap. Plant in the new hole with the crown a little lower than it was originally and water in with a root stimulant to help minimize transplant shock. Water and fertilize regularly during the growing
6. Is it true that clematis need a lot of lime to grow well?
Clematis have been regarded as lime-lovers ever since they were found growing wild on limestone. However, we have seen our native C. virginiana ramping happily over laurel and rhododendron in Willowdale State Forest where the soil is highly acidic. The truth lies in between - clematis grow and flower best in a good neutral
soil. If your soil is acid, you should definitely add lime which will make
the existing nutrients in the soil available to the plant. If your soil is very acid, and you haven't limed before, you may want to lime twice a year the first year (in spring and fall) and once a year thereafter. A light dusting under each plant in the root zone should be enough. This needs to be done regularly because the more it gets the more it consumes and needs. Remember that if you don't lime your clematis, any fertilizer is largely
wasted because without the lime it will not be available to the plant
We want to hear from you! Do
you have a question about clematis? No question is too frivolous!
mail it to Completely
Clematis Nursery, 217 Argilla Road, Ipswich, MA 01938-2617.