May is a time of great growth in the garden and an essential period for making those final preparations before the summer gets into full swing.
Summer bedding plants
Mid-to-late May is the best time to plant out summer bedding plants. Prepare the soil and use some organic compost to fertilize the soil ready for the new bedding. You do need to keep an eye on the long term weather forecast when doing this, as a late strong frost can put pay to your hard work. You can keep plants in the greenhouse until the weather improves and move them out towards the end of the month. Just make sure they're well watered and the greenhouse is well aired, vented and shaded during the day so that these plants don't over heat in warm weather.

The same rules apply for hanging baskets. You can plant these from April onwards, but until the last sign of frost has passed you may want to protect them in the greenhouse. If you don't have one, hold off planting until the end of May. Line your basket well and add a fertilizer rich compost soil. There are plenty of varieties to choose from but trailing plants work well for covering the sides of your basket. Water well, add fertilizer weekly and keep any eye out for pests!
Tidy up
You may find you need to clip any hedging and topiary now to keep its shape neat and tidy. The warmer weather will also mean regular mowing of the lawn will be a necessity now and through the summer months. Once a week should be sufficient, keep on top this and your garden will look tidy all summer!
It's also a good time to take stock of your wooden garden furniture. Choose a dry day to treat, stain or paint in order to prolong the life span.

Deal with weeds
As the temperatures rise your prized plants will spring to life, but unfortunately so will any unwanted weeds! Pull up any seedlings and dig out perennial weeds with a fork to try and get rid of any roots. Time and effort spent on these perennial weeds will benefit not only your borders but also your lawn, as May is the ideal time to identify those nasty dandelions and deal with them.
Pond
If you have a pond, pond weed is equally important to deal with and should be removed regularly before it becomes too difficult to manage and harmful to pond life. Make sure you leave any weeds by the side of the pond for a good while before removing just in case any pond life is hiding there!May is a great time to begin stocking ponds with fish, just make sure any aquatic plants have established first.

Keep an eye on growth
Many growing plants may need your attention this month, add plenty of feed to keep them happy. Tall perennials may need trellis and support as they start to grow to keep them straight and upright.It is also important to tie up your clematis to control their climbing in the direction you would like them to grow. For rambling roses, try and tie as horizontal as possible as this will restrict the flow of sap and increase side shoots, thus causing more flowers. Spring flowered Montana type clematis need pruning after flowering to keep them tidy.