NOW that autumn has arrived, many shrubs have finished flowering.

Hydrangeas however, seem to just keep on going. As some varieties finish, others are still in full bloom.

“Mophead” hydrangeas (Hydrangea macrophylla) and “lace-caps” (Hydrangea macrophylla normalis) are probably the most common garden varieties, with pink, blue or white flowers.

Mine has been flowering since the start of August and is still going strong! If you buy a blue flowering hydrangea and want to keep it blue, then you need an acid soil.

If you don’t know if your garden soil is acidic or not, and you don’t want to test it with a PH testing kit, then you could always add some ericaceous compost to the soil at the time of planting.

If growing in a pot, then plant it in ericaceous compost with a little bark or grit to help drainage.

Prune the old flower heads off in spring after the frosts have gone and you should have a magnificent display of flowers in the late summer, going right into autumn.

To ensure you have an extended flowering season, you might want to try growing hydrangea “Endless Summer”.

It has the advantage of growing on old and new wood, so if there is a late frost in spring, it will not spoil it from flowering.

As it only grows to around 1m (3ft), it is perfect for a container. There are three colours, pink, blue and white – which is branded as “The Bride” so makes a great gift idea.

Hydrangea paniculata, which can grow to over 1.8m (6ft) high, has slightly different shaped flowers, being conical as opposed to the rounded shape of the macrophylla types.

The varieties ‘Phantom’ and ‘Pinky Winky’ have white flowers, turning to pink as the flower ages. They are only small plants, growing to around 1m (3ft) high. These varieties need to be pruned harder in spring, cutting all the new growth down to around two or three buds.

Most hydrangeas require light shade, but some, such as hydrangea involucrate, prefer a sunny location, in well-drained soil.

It has a lovely blue or rose-pink flower and grows to around 1.5m (5ft) high.

This year, I have had a few customers asking why their hydrangeas have not flowered.

This can be for a few reasons. They could be too dry, fed with a high nitrogen-based fertiliser which promotes foliage and not flowers or pruned incorrectly.

A feed with a specific hydrangea fertiliser in spring should help.

If the hydrangea is planted in deep shade, the low light levels will also affect the number of flowers produced.

Hydrangeas really are tough-as-old-boots plants, that need very little attention once planted in a suitable position in the garden. They are easy to grow and reward you with colour right up to the first frosts.