Descriptions of bearded irises usually include reference to the three main parts; the Standards, Falls and Beards.

Standards: Upper three petals of Iris flower.

Falls: Lower three petals of Iris flower.

Beards: The line of fuzzy hairs at top of falls.

Hafts: Top part/shoulder of the fall surrounding beard.

Horns: Spear-like extension lifting up from tip of beard.

Rim/Edge: Thin edge of colour around Falls and sometimes standards.

Spoons: Spoon-shaped appendage extending from tip of beard.

Rhizomes: Underground stem. Roots and buds develop from the nodes. Often enlarged to serve as storage organ.

Increase: Also called Offsets. These grow off the rhizome to form a new plant.

 

Planting

When and where to plant

The best time to plant bearded iris is late January through April. Choose a garden bed in an open sunny location. Too much shade will produce heavy foliage, but little or no bloom. Irises do well in porous soil with a pH 6.5 – close to neutral. For best results some gardeners mix lime or dolomite into the soil a fortnight before planting.

For heavier, clay type soils, add aged compost, course sand and/or gypsum to the soil when preparing the bed, and plant irises in raised beds.

If you are unable to plant your irises right away store them in a cool dry place. The sooner the irises are planted, the more likely they will perform well for you the following Spring.

How to plant

Make a shallow hole about twice the size of the rhizome. Take a handful of the soil you removed and make a mound of soil in the centre. As in the diagram above, place the rhizome on top of the mound and drape the roots down the sides.

Press the rhizome down to ensure that it makes firm contact with the soil. When you fill the hole with soil, the top of the rhizome closest to the leaves should be at or slightly above the surface. Pack soil tightly around each rhizome. Water in and repeat every two days for a fortnight. Then continue watering as you would the rest of your garden.

When planting during very hot weather, it may be beneficial to shade the iris for a couple of days afterwards.

Arranging rhizomes

 

Irises are often planted in groups of three forming a triangle with the toes pointing into the centre.

The toe of the iris is the opposite end of the fan.

Space 30 cm apart with 45 to 60 cm between each group of 3 rhizomes.

If you prefer to plant in rows, space rhizomes approximately 45 cm apart and facing the same way. Irises will increase in the same direction without crowding each other.

Maintenance

Top dress in early Spring with a general purpose fertilizer. Be careful not to spread fertilizer directly over rhizomes. During Spring and Summer if the weather is damp you may need to spray for leaf spot and aphids. The same spray as you would use on roses is quite effective.

An organic method of dealing with sucking pests is using insecticidal soap (1/2 cup of dishwashing liquid mixed with 2 litres of water and sprayed onto the plants). With heavy aphid infestation, you may need to spray once with insecticidal soap, wait a few days, and spray a second time after new aphid babies have hatched

Keep rhizomes clear of weeds and dead leaf litter. Do not mulch close to irises as this can cause the rhizomes to rot. The sun should be allowed to shine on the rhizomes to help initiate next season’s flowering.

Dig and divide iris clumps after their third flowering season. Keep the vigorous growth and discard rhizomes which no longer have roots. Preferably shift the new plants to a newly cultivated bed and or another location.

Iris bedfellows

The Greek word Iris means ‘rainbow’ and there is an iris for every garden colour scheme you can imagine.

You might wish to select irises that repeat a colour from one iris to another. For example the bi-colour, Ride the Wind has white standards with blue falls. It looks great near the dark blue Dusky Challenger and a multi-colour blue/purple iris such as Share the Spirit. White irises such as Jayceetee, intensify the colours in all shades.

Iris leaves add a strong texture to other soft perennials. The spiky leaves add drama and height. Some iris leaves even have a purple colour at their base. Here the white iris Bubbles Galore adds dramatic effect to a row of salvia called Hot Lips.

If you have any queries regarding growing and maintaining our irises, please feel free to contact us.