Posted: Today at 12:29
You can buy SB from many suppliers. Due to its good results, its popularity is spreading. I shop around on Amazaon and gardening sites for the best deals, as I get through a lot. That said, I buy a huge bottle and dilute it down (it's about 10ml of SB to 1 litre of water) so it does go a long way. As long as you're patient and thorough - and always respray after it rains, you'll see a marked difference in very little time. My plants also look healthier and stronger - which is a bonus, as the stronger they are, the less they are susceptible to attack from other pests.
I find that the aphids on my roses are 100% controllable and it also controls red spider mite and thrips, to some extent, but if I miss a week of spraying, it can slide backwards.
Blairs is right - legally, you are allowed to remove any part of a plant that overhangs your garden - might be worth considering with this tree, also to open it up and give the plants under it more light.
Lucy - I found that ladybirds are really good, but sadly there weren't enough aphids in my little garden to feast on (this was before I'd used SB) so they hung around a bit and flew off. That was an expensive trial for me
Could be a really good idea to set up ladybirds in the aphid tree though, possibly sticking a house for them under the tree itself....then using SB on your plants Sharon? That way, the ladybirds are incentivised into staying, as they have loads to eat on the tree, which is hard to spray as well and your plants underneath get a good foliar feed and chance with the SB.