September is a very interesting month in the Dahlia garden. The tubers are beginning to show signs of life once more, and the soil is starting to warm up.

If you have a hot bed, you can start warming up the tuber clumps to produce some early cuttings. A mixture of sand and peat works very well here. Quite a few growers do this every year, and don't actually plant any tubers at all. Green plants can be planted up to a month or so later than tubers, and they catch up on the tuber growth quite readily. Tubers can now be removed from their sawdust boxes, and put in a warm place. Some growers cover the base of the clumps in a mixture of moist sand, peat and potting mix, to warm the tubers up and encourage them to sprout. Even putting the clumps out under a protective tree or hedge will help start them off.

Dwarf and Miniature growing varieties can now be planted into pots or containers. Put a small sprinkling of slow release fertilizer pellets in with the soil or container mix, and this will give them a good boost during the flowering season.These types of Dahlia are prolific bloomers over a long period, so to keep up this flower production you need to pick off the dead heads very regularly. Bees love these Dahlias, as a lot of them are single, waterlily, anemone or collerette types with open centres, which give easy access for nectar. Some varieties you can just give a gentle tug and the dead flower head will come away, but others such as the variety "Robert" need to be snipped off. To keep your plants tidy, it is just as easy to snip all dead heads off, and by cutting down to the next bud you won't get left with a lot of woody stems which will detract from the appeal of these little plants. Don't forget to sprinkle your pots with a few slug and snail pellets, as slugs particularly love things in pots.

Your seedlings can now be planted if they are of sufficient size and maturity, and the ground has warmed up. They can be planted much closer than your main crop Dahlias. About 9 inches apart, and a foot or so between the rows is sufficient. Tie them up to a cane or long string between canes for a bit of support as they grow. Don't disbud, but just let them grow straight up. When they produce their first flower, decide whether you want to let them continue on. If they weren't satisfactory in form, i.e. single, muddy coloured, or just weren't up to standard or what you actually hoped for, pull them out and give the remaining plants a bit more room. Label any that you consider show promise, and retain them for the following season. It pays to cull quite hard here, otherwise you will find that you have so many the next season that don't make the grade, but still require the same amount of work and sprays etc. as your good ones.It is better to have a few good quality plants, than a large number of "also rans."

Apply your fertilizers about six weeks before planting your main Dahlia beds. Most growers use a rotary hoe, or manually dig over their beds before applying animal manure, mushroom compost, or the fertilizer of your choice.