HOW TO GROW IRIS BULBS

How to grow Iris bulbs

Although still under discussion, the Iris genus is believed to contain between 250-300 species. Of course most people will think of the large, herbaceous flag iris with their large exotic, and brightly coloured flowers but the small bulbous species are as beautiful and intricate as any of their larger cousins.

Iris bulbs

For the cooler regions of northern Europe species from the reticulata group are the hardiest and therefore will be the most suitable for overwintering. Further south and iris from the little-known Juno subsection will be worth planting.

Avoid planting Iris from the Xiphium subsection unless you are in a region that experiences mild winters or if you intend to grow them in a pot with the view to bringing them in under protection.

Plant Iris reticulata bulbs in clumps 2-3 inches deep in September or October. They are best grown in a light, well-drained and chalky or limestone soil. They are ideal for planting in a rockery, alpine bed or at the front of a herbaceous border. Avoid planting in heavy soils as the bulbs can become damaged if overwintered in waterlogged conditions.

After flowering in the spring, feed with a liquid soluble fertilizer once a month but only during the growing period. This will help to produce bigger bulbs for the following spring and subsequently a better flowering display.

Pot grown Iris

Iris 'Katharine Hodgkin'

Plant 6 bulbs, 2-3 inches deep, in a 5 inch pot using a good quality compost such as John Innes 'No 3'.

Come the winter they can be brought into an unheated greenhouse until the spring. If you are growing Iris in pans or bowls for a spring table display do not be tempted to bring them into a warm room until the buds are showing full colour. bring them in too early and the buds will dry out and fail to open. However the atmosphere of a greenhouse will usually prevent the buds from drying out.

For related articles click onto the following links:
RHS Iris
HOW TO GROW THE BEARDED IRIS
HOW TO GROW BULBS
HOW TO GROW GLADIOLI
HOW TO GROW GLADIOLI FROM SEED
HOW TO GROW HELXINE SOLEIROLII
HOW TO GROW IRIS RETICULATA
IRIS 'KATHARINE HODGKIN'
IRIS RETICULATA
WINTER ACONITE - Eranthis hyemalis