How to grow Siberian iris 'Helen Astor'
Keep in mind when planting that Helen Astor is thought of as very hardy, so this plant will tend to survive through freezing conditions.
Growing Helen Astor from seed
Transplanting Helen Astor
As Helen Astor is very hardy, ensure temperatures are mild enough to plant out - wait until after your last frost date to be on the safe side.
Harvesting Helen Astor