Larkspur needs both cold stratification to break seed dormancy and trigger germination and vernalisation (a period of cool growing temperatures) to trigger flower development.
Larkspur won’t germinate if the soil temperature is higher than 13°c so it’s vital that seed is sown outside in an unheated greenhouse and definitely not placed on a heat mat.
Upon receipt from our autumn jump starter seed shop, pop your larkspur seed packets in the fridge or freezer until the weather starts to cool down.
This will treat seeds to cold (stratification) which will help break seed dormancy.
For best results sow in October.
Sow one seed per cell. Larkspur has a tap root that can be delicate. By sowing seeds in cells this limits any need to disturb the roots.
Cover seeds with a layer of compost to block out the light, darkness aids germination.
It is important not to overwater seed trays, Larkspur seeds are prone to rot. If you find any of the cells are empty after a few weeks, simply sow another seed.
You can keep sowing seeds until January if needed. More information can be found in our Handbooks.
For the longest vase life cut Larkspur (Delphinium consolida) when one-third of the blossoms are open.
For drying cut Larkspur (Delphinium consolida) when two-third’s of the blossoms are open.
Of course when cutting for yourself you can cut blooms whenever you like, the vase life May be shorter but you’ll get the benefit of both the garden and an indoor display.