- Cannas do best with a good supply of water, so water the plants during the summer if the rainfall is less than 1 inch per week. Water freely in a dry spell.
- Keep a thin layer of mulch around cannas to help retain moisture as well.
- Stake tall varieties if needed.
- As flowers fade, deadhead to promote continued flowering.
- After autumn frost blackens the foliage, remove the stems and leaves. See your local frost dates.
- Cannas are winter hardy in zones 7 to 10. Otherwise, you need to lift the rhizomes for winter storage. Store in barely-moist peat or leaf mold in frost-free conditions. Space rhizomes so that they are not touching.
PESTS / DISEASES
- Slugs, snails, spider mites, and caterpillars may be problems.
- Rust, fungal leaf spot, and bacterial blight are common.
- Bean yellow mosaic and tomato spotted wilt viruses can occur.
HARVEST / STORAGE
- If you need to lift your cannas, do so right after the first killing frost. Dig one foot away from the stem so that the rhizome (roots that shoot) is not damaged. Loosen the soil and lift out the clump. Shake off the dirt and cut off the tops.
- Store cannas over the winter in a dry place at 45 to 50 degrees F (often an attic or basement). Don’t let them dry out; sprinkle the sand or soil around them, if necessary.
- In early spring after the tulips have bloomed, divide the roots. Make sure that each divided piece has at least one eye, where new leaves will grow next year. Then plant 4 to 5 inches deep and 1 to 4 feet apart. They will bloom in 10 to 12 weeks.