Clematis Plants, vines and climbers from UK online store, Raymond Evison Clematis Ltd

Breeding And Assessment

The breeding and assessment of new clematis cultivars is an exhaustive process that takes ten years from pollination to production.

Each year 2,500 crosses are made resulting in 25,000-35,000 seeds.

Approximately 6-8,000 germinate but 98% of these are likely to be rejected at the first assessment stage.

The selected seedlings then undergo a further 8-10 years of assessment, monitoring and secondary selection.

At any time the pool of plants undergoing these secondary tests represents a quantity of 600 different cultivars.

Final testing is undertaken by growing the plants outdoors in Denmark and the UK.

Only 1 or 2 of the 25,000+ seeds are likely to make it past these assessments and be offered for sale.


One of the 2500 annual controlled crosses being made Up to 35,000 seed matures over a 9 month period Raymond and Mogens Olesen of Poulsen Roser A/S making secondary assessments Chris and Dace

One of the 2500 annual controlled crosses being made