Growing lavender from seed is supposed to be difficult and, from what I’ve read, not really worth it. Seeds can take up to three months to germinate (if they do at all) and plants that come from seed are not always true to the parent plant (only propagtion by cuttings can achieve that). However, despite all that, I decided to have a go anyway, just for the sheer hell of it – and because I had a packet of Munstead Lavender all ready and waiting to be used.
So, for those who also wish to try this method, here is a step by step guide.
1. Make sure that your seeds are from a reliable merchant (mine were from Thonpson & Morgan) and have ready a reliable seed mix compost and a good propagator. As far as propagators go, I used a compact plug plant trainer from Agralan, which can produce up to 49 plants in a small space.
2. Fill up the propagator container you will be using with good seed compost. I used John Innes Seed Compost, although because it contains peat, I will be searching for a good environmentally friendly alternative in the future). Level off the top of the soil and make a small impression in it for each seed you want to sow.
3. Lavender seeds are very tiny and fiddly, but if you are careful, you can get one in each depression – most of the time anyway! Then just scuff the edges of the depression over the seed – or sprinkle lightly with vermiculite if you prefer.
4. Give the seeds a good watering and place the propagator lid on. Put the propagator in a bright, warm place and keep it at about 15-20 degrees C or 59-68 degrees F. Germination can take up to five months, although my seeds have always germinated within two weeks.
5. If you keep the propagator lid on, the seed environment seems to regulate its own moisture and you will hardly have to water. However, if the soil is getting dry, just give it a sprinkle of the old H2O and put the lid back on.
6. When the seedlings are large enough to handle (I like to see at least 4 leaves), transplant them carefully into 3″ pots and place them in a cooler area. I put mine outside in a mini greenhouse where I can raise the doorcover on warm days and close it at night or in colder conditions.
7. When they have reached a good 2-3 inches and look strong, you can plant them outdoors – just as long as there is no risk of frost.