Clematis from the Olbrich Botanical Gardens

Clematis 'Betty Corning' and a Jackimanii-style clematis, possibly 'The President' or 'Lady Betty Balfour'-- both rich, deep purples known to grow well in the Chicago Botanical Gardens' trials.

Growing clematis in central Wisconsin is a matter of picking the correct cultivars, waiting for the plant to mature, properly siting them, and providing for their other cultural requirements.

To assist in choosing the right cultivars for your area, a good way to go about this might be to see what is growing well for other gardeners in your area. Unfortunately, the period of time between purchase of the clematis and when it starts to show its beauty is just about 3-4 years, long enough that unless careful marking or records are kept most gardeners don't know the name of the clematis now growing in their garden.


Clematis 'Betty Corning' - Clematis viticella or Italian clematis

Another way to go about it might be to research cultivars through your nearest public or botanical gardens. You might visit the garden during peak bloom record your choices. They are more apt to be labeled there. Then, wait until the next planting season and pull out your list.

Another might be to check out clematis trials done at various test gardens around the area.

Clematis texensis 'Princess Diana'

Clematis do not grow well in a northern exposure and I would recommend against siting them there. In the South, clematis are not planted with a southern exposure because of the heat. Here in central Wisconsin this is not a problem. Clematis should be planted so as to receive as much sunlight as possible. They also like a lot of moisture. Clematis should be planted deep as well, with as many as 2-3 leaf nodes below the soil surface. Since clematis like moisture, if you have not planted your clematis nice and deep to start, a nice thick layer of mulch will help both of these cultural requirements.

Clematis are heavy feeders as well and other than roses and hydrangeas may require more nutrients than nearly any other perennials in your garden. Watering the roots rather than overhead watering can be beneficial in controlling fungal diseases.

Sometimes gardeners will ask how to prune their clematis. These is generally followed by me with the question as to which cultivar they might wish to prune.

This is where it gets dicey. They don't know which clematis they have. Sometimes they will know exactly what color their clematis is versus "a lavender-purpley color?" or when it blooms versus a bloom time of "summer?".

At this point, I really have to tell them, "Did you like what it looked like last year?"

"Yes."

"Did you prune it?"

"No."

"Alrighty then, leave it alone."

So often we just want more than we rightfully deserve. If your clematis is thin at the bottom and bushy at the top (this is the way clematis have a tendency to grow, by the way), mulch it heavily, feed it regularly, water the roots.

Be happy.

Clematis can be a bit scary to prune. Here in central Wisconsin, clematis can be a bit slow to begin growing. I wait until I can see buds forming in the leaf axials before I attempt to prune out any dead wood from the previous growing season. Left to its own devices the clematis will use the dead structure from the previous year as scaffolding for this years growth. I typically prune only for shape. If I want to develop a bit bushier plant I will pinch out just the very top growing tip, at a 4' to 5' height. This keeps me out of trouble and my clematis flowering every year. Some of the clematis in my garden will have double blooms early and a later set of single blooms because they flower on old and new wood.

The only clematis in my yard which I cut nearly to the ground are clematis 'Sweet Autumn, which flowers on new wood and the bushy versus vining clematis intregrifolia 'China Blue'.



All pictures were taken at the Olbrich Botanical Gardens.

Tomorrow: Pictures of Clematis Which Grow Well in My 4b/5a Garden(the USDA has updated my zone!).