Posted: 02/02/2015 at 10:18
You really do need to separate them if they are ever to perform well as, apart from their very different flowering and pruning regimes they will be competing for limited food resources. Clematis are very hungry, thirsty plants and need loads of food to do well as well as adequate moisture.
Can you not buy another pot?
The group 1 will naturally produce buds high up on old growth and will do this early as it flowers in spring. To renew it and encourage buds lower down you need to remove a main stem to the ground every year once flowering is finihsed and then prune all stems back to a tidy framework. This encourages the plant to produce healthy new growth at all levels and thus flowers each spring. They can also be left unrpuned but then you will only get flowers at the top. Either way, the best tip for flower power is clematis food given in generous dollops in early sprng and some liquid feeds of tomato food.
The group 3 will show buds lower down when it starts in to growth. It's still very early so patience is required. You then cut back to just above these buds and remove all the top growth and feed as above but, as they flower for longer, feed more generously.
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