Sow seeds 6 to 8 weeks before your last spring frost. This gives them a head start for early summer blooms.
Directly sow seeds into the garden after all danger of frost has passed and the soil has warmed completely.
Fill seed trays or peat pots with a lightweight, sharply draining seed-starting mix.
Press seeds 1/8 inch (3 mm) deep into the soil. Unlike Rodgersia, Limonium seeds require darkness to germinate, so cover them lightly with a thin layer of soil or vermiculite.
Mist the soil gently so it is damp but never soggy. Excess moisture will cause the seeds to rot.
Place the trays in a warm room at 20°C to 21°C (68°F to 70°F). Once the green sprouts emerge, move them immediately under bright grow lights or to a south-facing window.
