Q.clematis
I have an Earnest Markham growing against my single story wall. It has reached the top and wants to continue to grow, but it has nowhere to go. Can I cut the tips off and hope flowers will appear lower down on the plant?

Clematis growers believe pruning is an essential part of raising clematis. Ernest Markhams are the type that flower in late summer from new growth. Here are a couple of article that will tell you more about pruning your plant: https://www.gardeningknowhow.com/ornamental/vines/clematis/pruning-clematis-vines.htm
http://www.ces.ncsu.edu/depts/hort/consumer/quickref/vines-groundcovers/clematis-pruning.html