Propagate by cuttings, division or separation - Take root sections when the plant is dormant and place vertically in loose propagation medium in flats placed in a cold frame.

Divide the plant as desired in the spring. Fall division is usually unsuccessful.

Water during summer dry spells. Plants do not tolerate drought well.

Tall varieties may need staking.

Remove faded flowers to improve appearance. Deadheading not needed to prolong bloom.

Cut plants back to the ground after hard frost. Do not divide in fall.

Provide excellent drainage and mulch to assure overwintering. Plants may be shortlived if overwintering conditions are too moist.

Divide in spring as needed to control spread. Plants are often slow to establish, but if conditions are right they can spread aggressively.

More growing information: How to Grow Perennials

More growing information: How to Grow Bulbs

Japanese beetles
Flea beetles
Black blister beetles

Downy mildew
Leaf and stem smuts
Septoria leaf spot
Powdery mildew
Rust
Synchytrium leaf gall

Numerous varieties come in a broad range of sizes. Flowers can be single, double or semi double.

‘Honorine Jobert’ has abundant blooms that are single and pure white, with pink tinted undersides and showy yellow stamens.

‘Kriemhilde’ has semi-double violet-pink flowers with undersides are a shade darker.

‘Lady Gilmore’ has double rosy-pink flowers.

‘Luise Uhink’ has semi-double pure white blooms. Strong performer.

‘Max Vogel’ has single, pale pink blooms that turn nearly white with time. Outer petals are slightly darker.

‘Montrose’ has semi-double to double rose flowers

‘Pamina’ has double rosy-red flowers.

‘Profusion’ has semi-double rosy-pink blooms. Strong performer.

‘Queen Charlotte’ has large semi-double pink flowers with darker undersides.

‘September Charm’ has single blooms that are rosy pink. Strong performer.

‘Whirlwind’ has semi-double white blooms, with contorted greenish-white inner tepals.

‘White Giant’: grows 4 feet tall with large semi-double flowers.