Canna 'Roi Humbert'

Autumn - mid · Planting

Lift before winter

Carefully dig out of ground or remove from pot, avoiding damage to the rhizome. Remove excess earth, give plant a dusting of fungicide. Pack bark chips around rhizome and ensure it doesn't dry out during winter. Keep in a cool, frost free area.

The plant will die if the roots are frosted, so it is essential to lift the plant before there is any danger of a frost.

Spring - late · Outdoors

Feed with sequestrol

If plants are acid loving and grown in soil with little acidity, or in a container, or are watered with limey tap water an annual feed with sequestrol (iron chelate) is highly beneficial. Follow guidelines on the packet. Will also 'blue-up' hydrangeas.

For hydrangeas that have good blue flowers in acid soil, this product can be used with alkaline soil to turn the flowers blue. This is most effective when the soil is neutral or just slightkly alkaline.

Spring-Autumn · Outdoors

Water to keep the soil moist

For best results, this plant needs soil that is always moist. Water deeply and regularly as soon as soil appears dry. Even for established plants in the ground, a dry week can cause problems with some soils. Check plants in pots more often, especially in hot weather. Or install an automatic irrigation system which will do the hard work for you, even when you are away on holiday.

Without regular watering some plants never fully regain their beauty.

Summer - early · Outdoors

Apply slow release fertiliser

Apply a slow release fertiliser which is spread around the root area of the plants soon after they have come into growth. (Or apply a liquid feed at regular intervals throughout the growing season.)

This is a simple way to provide a nutrient boost as a single annual procedure.

Outdoors

Water with rain water

This plant needs rain water or soft water (the minerals in alkaline or "hard" water are harmful). This is especially important for plants in pots.