Bearded Iris

Bearded Iris Catalogues are beginning to appear in our mail boxes, so it might be time to have a quick look at their requirements. Depending on your soils and climate how you plant and prepare now will determine the success you have over the coming years.

From the onset, might I say that I never have trouble with any Iris disease mainly due to healthy soils which are quick draining. When I do have the odd disease, instead of reaching for chemicals, I generally discard the affected plant.

Chemicals generally mean to me that in the first instance, the growing conditions were not right for that plant. If this is the case, change the position and see how you go.

Traditionally gardeners are told to place their iris rhizome on a mound in your planting hole to facilitate good drainage and never plant them too deeply. The soil should just cover the top of the rhizome as Iris will not tolerate wet feet. This holds for colder climates but just does not need to be done in warmer winter regions with light soils.

The situation in which your new plants grow should receive at the very minimum five to six hours of direct sun each day; meet this and you are laughing.

At planting time, please do not include fertilisers as this will often make them bolt and not flower, it also can lead to the rotting of your rhizome.

As I keep harping over the past year, sun, soil and drainage are the key factors to your success.

At least a month before planting, the new home for your iris should be fertilised with dolomite, nitrogen, potash, and phosphorus as these are essential for your Iris's well being. Talk with your local nursery regarding the correct balanced fertiliser, something along the lines of a low-nitrogen fertiliser such as 5-10-10 is fine.

Iris will grow in a wide variety of soil types but a light, loamy soil with a pH of 6 to 7 that has been amended with organic matter is best. A tight clay soil may keep the rhizome too wet and should have organic matter such as composted pine bark, sea weed; they love sea weed, incorporated to improve drainage.

Manures such as dynamic lifter will work if added to your bed well in advance, though I don't recommend this for established iris beds.