How to grow bulb irises

Choosing bulb irises

All you need to decide is when you need colour in your garden – to start the year, or to accompany summer-flowering plants.

Iris × hollandica types reach 60cm (2ft) in tall when in flower and have unobtrusive grassy leaves. Colours range from yellow, blues, purples, whites and bi-coloured flowers.

Iris reticulata is diminutive in stature at 15cm (6in) and flowers in February to March to start the year. The leaves die away in summer when the bulbs

These are fleshy, rounded, underground storage organs, usually sold and planted while dormant. Examples include daffodils, tulips, hyacinths, lilies, onions and garlic. The term is often used to cover other underground storage organs, including corms, tubers and rhizomes. are dormant

Dormancy refers to a period of inactivity in plants, during which they slow down or stop their growth, conserving energy and resources. This is a natural process that helps them survive harsh conditions, such as winter or drought. Dormancy in seeds is a mechanism that prevents them germinating until environmental conditions are favourable for growth. .

Where to plant bulb irises

Plant in well-drained soil in a sunny position.

When and how to buy bulb irises

You can buy iris bulbs

These are fleshy, rounded, underground storage organs, usually sold and planted while dormant. Examples include daffodils, tulips, hyacinths, lilies, onions and garlic. The term is often used to cover other underground storage organs, including corms, tubers and rhizomes. in September and October by mail order, in nurseries, garden centres and DIY stores.

Sometimes you will see potted Iris reticulata types for sale in garden centres when they are flowering in spring; this is more expensive but you get instant enjoyment.

Planting

Choose a sunny position where the soil is well-drained. Iris reticulata planted en mass under a tree canopy can create an impressive spectacle to herald spring.

Plant bulbs as soon as possible after purchase. Planting them up to 15cm (6in) deep can help encourage your bulbs to reflower more reliably the following year. Space about a minimum of 5-7.5cm (2-3in) apart.

Plant potted bulbs just as you would for other perennials, with the compost

Can refer to either home-made garden compost or seed/potting compost: • Garden compost is a soil improver made from decomposed plant waste, usually in a compost bin or heap. It is added to soil to improve its fertility, structure and water-holding capacity. Seed or potting composts are used for growing seedlings or plants in containers - a wide range of commercially produced peat-free composts are available, made from a mix of various ingredients, such as loam, composted bark, coir and sand, although you can mix your own. on the top at the pot finishing just below the soil surface.

Routine care

Happily, these irises are very low maintenance. However, it’s best not to consider Iris reticulata as long term plants, especially on a soil that isn’t perfectly well-drained. Dutch iris are more reliable especially on a well-drained soil. Replacement is cheap and bulbs

These are fleshy, rounded, underground storage organs, usually sold and planted while dormant. Examples include daffodils, tulips, hyacinths, lilies, onions and garlic. The term is often used to cover other underground storage organs, including corms, tubers and rhizomes. are widely available.

No actual pruning or deadheading

Deadheading is the process of removing spent flowers from plants to encourage more blooms and prevent seed production. This helps to redirect the plant's energy into producing more flowers rather than producing seeds. is required. The foliage will die away naturally after flowering so just pull away the foliage once dead and straw-brown. At this stage, you may want to mark where the bulbs

These are fleshy, rounded, underground storage organs, usually sold and planted while dormant. Examples include daffodils, tulips, hyacinths, lilies, onions and garlic. The term is often used to cover other underground storage organs, including corms, tubers and rhizomes. are (such as with a cane

A cane is a slender, straight, length of woody plant material, usually bamboo. Canes are primarily used as plant supports. The fruiting stems of blackberries, raspberries and hybrid berries (such as loganberries and tayberries) are also known as canes, so these crops are often referred to as cane fruit. or label) to prevent you digging them up by mistake.

You can divide the bulbs

These are fleshy, rounded, underground storage organs, usually sold and planted while dormant. Examples include daffodils, tulips, hyacinths, lilies, onions and garlic. The term is often used to cover other underground storage organs, including corms, tubers and rhizomes. of Dutch iris and Iris reticulata types in autumn. Each single bulb tend to split into many ‘daughter bulbs’. Pot these small bulbs into 7.5cm (3in) pots with a mix of peat-free John Innes No. 2 compost

Can refer to either home-made garden compost or seed/potting compost: • Garden compost is a soil improver made from decomposed plant waste, usually in a compost bin or heap. It is added to soil to improve its fertility, structure and water-holding capacity. Seed or potting composts are used for growing seedlings or plants in containers - a wide range of commercially produced peat-free composts are available, made from a mix of various ingredients, such as loam, composted bark, coir and sand, although you can mix your own. and 10% horticultural grit by volume.

Water the compost to keep moist from autumn to late spring to support good development. They can take a couple of years to reach flowering size.

Although iris are usually trouble-free, slugs and snails sometimes favour bulb irises