Lavender

Quality

I am planning on planting approx 20 lavender plants as a border to a wall out my back garden.

I was hoping to grow these from seed. I am not in a majir hurry to have garden finished. But if its gonna take too long I won't bother with the sowing myself

I understand I will have to sow seeds indoors. I will have access to a glass house in spring.

So how long would you think I will need for them to grow before they can be planted outside?

Mo60

I have grown lavender plants from seed and found it took 2-3 years for plants to establish. It might be quicker to buy a lavender plant and take cuttings.

lottpaul

I agree with Mo60 - growing from seed is possible but takes a while to get to the stage of viable plants.
Cuttings would be much quicker and you can be sure the plants will be true to their parent. You might be lucky enough to have a generous neighbour or friend and be able to get lots for free. If you're aiming for 20 plants I would take at least 30 cuttings. If they all take, you will have some to give away or keep as potted specimens.

Quality

That's great. When is the best time of year to take cuttings?

Mo60

You could take some cuttings now. If you google 'lavender cuttings' you will get all the information you need.