Why do the English let there bushes grow, and not cut back on them.?
Answers:
Your question is generalizing the English and is not all that clear but here goes. Most people whether English or from somewhere else cut their bushes at first to enable them to fill out. Once that has been accomplished each individual person decides what purpose they want them to serve. Perhaps for division or privacy. It's a personal taste matter not because of being English.
Other answers:
What do U mean?
How does UR garden grow, if U keep cutting them back all the time?
What do U mean?
How does UR garden grow, if U keep cutting them back all the time?
Some people like a very manicured look to their yards, and spend countless hours trimming and pruning everything. Some people like a more wild and untamed look and let things grow unchecked for years. Some people do a little snipping here and there, but let plants reach their proper size. It just depends on who is in charge of the garden!
I live in the USA and I currently have a wild looking yard, with arbors overhead and greenery extending in all directions. Every winter my yard dies way back, but come summer, things get big and bushy, and I like it that way. More power to wild looking places!