As someone with legal training, I’m hesitant to make such a broad claim, but I am pretty sure I am safe with this one:* Anyone can grow Iris in a pot. If you can add water when the soil is dry, you can have a beautiful one of these…
The ideal time to buy iris rhizomes (fat roots that look sort of like fingerling potatoes) was back in August and September, but you should still be able to find rhizomes in your garden center. When you head out to the garden center, you will probably find rhizomes with clipped roots and leaves. The rhizome should be firm; it should not be dried out, mushy, smell bad, or have holes from insect damage.
Planting and caring for Irises is really easy:
- A 6″ to 8″ pot will work for Dwarf Iris; a 12″ pot will work for Tall Bearded Iris. Make sure your pot has good drainage (i.e. a big hole in the bottom or several smaller holes).
- For soil, choose a fast draining, light potting soil.
- To plant, dig two shallow trenches with a ridge between them. Put the rhizome on the ridge and spread the roots carefully in the trenches. Cover the roots and rhizome with dirt, but don’t bury deeply. The top of the rhizome should be very near the surface and the leaves should be above ground.
- Put the pot in a sunny location.
- Water only when the top two inches of soil are dry (it’s better to water too little than too much with irises).
- Fertilize one month before blooming with 5-10-10 fertilizer. Bearded irises generally bloom in May and June, dwarf irises in April. Check the tag of your particular iris for a more precise bloom time.
If you live in an area with mild winters, you can leave the pot outdoors for the winter. But if you have “real” winters, bring the pot inside and find a sunny spot. Since this is a bit late to start irises in temperate climates, they might not have enough time to get established before winter. But next year, you can leave the pot outdoors with a protective layer of straw or leaf mulch or something similar.
If you forget to water or fertilize, don’t worry, your iris is most likely fine. I know my grandma didn’t fertilize her irises and they still bloomed like clock work. Many varieties of iris can even tolerate partial shade.