Posted: 02/08/2017 at 15:22
Hi Devonian and welcome
Normal multi-purpose compost just won't do the job ... it's fine for growing on veggies and containers of summer bedding, but for plants in permanent planters you need a loam-based compost ... my lollipop bay is in John Innes No 3 mixed 3:1 with horticultural grit to improve the drainage.
I also wouldn't grow anything else in with my bay ... I understand the look you're trying to achieve but it's going to take a lot of maintenance and tlc. The lavender will compete with the bay for water and nourishment.
My bay is in a terracotta container of a similar size to your half barrel, raised up on feet to aid drainage, and topped off with horticultural grit ... we water it with a bucket full of water every few days from March onwards, feed it with dilute seaweed fertiliser every few weeks through the growing season and re-pot it every other year using fresh compost. (It's a two-person job )
Hope that's helpful
Last edited: 02 August 2017 15:22:58