Bearded Iris grow from rhizomes and will growing best in a climate where they get a cold winter. They are a really easy iris to grow if you follow a few basic rules.
Position and soil are the two main factors.
Requiring a sunny position and a well drained soil, prepare the area to be planted by digging in well rotted compost and aged cow manure 3-4 weeks before planting. It is important to choose a position where the rhizomes will receive sun and will not be in competition with other plants.
Drainage is important when growing bearded iris, so in clay soils use some gypsum to help break up the clay, rhizomes that receive to much water will rot. In such soils consider mounding the soil so that the bearded iris rhizome sits up a little.
Remember that the rhizome itself is planted so that the top of it sits above the soil, not under it. We suggest planting in groups of 6 or 7 to create a good clump, the flowers look great en mass. Mulch around, but not right up to the rhizomes.
Dwarf Bearded iris are planted in the same manner.
Bearded Iris Cultivation Summary Information.
Planting Bearded Iris
The best time to plant Bearded Iris bulbs is in autumn or in early spring.
- Rhizomes must be planted with the top 1/3 showing above the soil level.
- Bearded Iris rhizomes should be planted about 35 cm to 45 cm apart.
- Position – Full sun.
- Soil – Humus rich and well drained.
- Newly planted rhizomes will need to be watered in well.
After Care for Bearded Iris.
- Commence watering when new growth begins in spring.
- Maintain some moisture until the foliage begins to die back after flowering.
- Fertilise with a general purpose slow release type fertiliser in early spring.
- Top dress with some blood and bone in late winter.
- You can cut the foliage back after flowering by 50% if you wish.
- Divide clumps every 3 – 4 years to maintain a vigorous flowering habit.
Dividing Bearded Iris
As clumps become established they will need to be divided to maintain strong growth and flowering. Usually every 4-5 years. The best time to do this is in spring, however you can actually divide them at any time that they are not flowering, in hot summer months you would need to take extra care and try to provide some shelter. Foliage is cut back to around 30cm at this time.
Can you grow bearded iris from seed, yes. You can collect seed from ripened seed pods of any iris, however they will probably not come true unless they are a species. Seeds can be sown in autumn and require a cold winter to assist with germination.
Iris do not actually require a lot of fertilizer, however this will differ from location to location. A liquid fertilizer such as a seaweed based product in spring is useful. Some slow release fertilizer or Blood and Bone can also be used. Try a low nitrogen fertilizer to prevent the plants putting on leaf growth rather than flowers.
Growing Bearded in pots and containers
Yes you can, although the dwarf species are best unless you have a large container, the same rules apply, good drainage, sun and plant the rhizome on the surface, the roots spread out and under the surface. Try not to over water.