Here are some garden jobs to do in the UK during the month of September:

1. Harvest: September is a great time to harvest many vegetables and fruits, including apples, pears, plums, beans, peas, and tomatoes. Be sure to pick them at the right time and store them properly.
2. Plant Spring Bulbs: September is the perfect time to plant spring-flowering bulbs such as daffodils, tulips, crocuses, and hyacinths. Plant them in well-drained soil and in a sunny or partially shaded area.
3. Lawn Care: September is a great time to take care of your lawn. Scarify, aerate, and feed it to help it grow strong and healthy.
4. Prune: Prune summer-flowering shrubs and trees to help them maintain their shape and to encourage growth for next year.
5. Cut Back Perennials: Cut back any dead or damaged parts of your perennials to keep them healthy and tidy. Leave some foliage to help protect the plant over winter.
6. Plant Trees and Shrubs: September is a good time to plant trees and shrubs, as the soil is still warm and moist from the summer months. Water them well after planting.
7. Clean Up: As summer comes to an end, it’s a good idea to start cleaning up your garden. Remove any dead or dying plants, fallen leaves, and other debris.

By completing these tasks, you can help prepare your garden for the autumn and winter months and ensure that it is healthy and productive for the next growing season.