About this product
Read this before you order: these sachets prevent fuchsia gall mite, they do not cure it. Each one holds a breeding colony of Amblyseius andersoni predatory mites that emerge slowly over four to six weeks, which is exactly right for meeting the pest as it wakes from hibernation, and far too slow to overwhelm an infestation that has already taken hold.
If your fuchsias are already showing distorted growth, cut the worst of it back first to remove the bulk of the pest population, then introduce predators. For an active infestation Phytoseiulus persimilis moves faster. Keep the sachets for what they are good at, which is being in place before the problem starts.
Fuchsia gall mite, Aculops fuchsiae, only reached British gardens around 2007 and is still spreading. The mite is microscopic but the damage is not: twisted, swollen growing tips that cannot unfurl, thickened deformed leaves, reddish discolouration, almost no flowers, and eventually a dead plant. The mites overwinter inside dormant fuchsia buds and emerge as temperatures rise, typically March in the south and April further north. That is when the sachets need to be already hanging, not when you order them.
The sachet has a small opening and the colony breeds inside it, so predators keep trickling out across the whole emergence period rather than arriving in one useless burst. Once out they climb over leaves and stems hunting mites and eggs. When the pest population drops, predator numbers fall back to a background level on their own.
Amblyseius andersoni works from 6°C to 40°C, and that range is the entire reason it suits this job. Most predatory mites only function in warm summer conditions and would still be dormant when fuchsia gall mite is emerging. It is also a generalist that will live on pollen when prey is scarce, so the population persists through the lean spells instead of crashing the way a specialist does.
It is not fuchsia-only. The same sachets work on red spider mite, both Tetranychus and Panonychus, pear blister mite, rust mites, box mite and thrips. Live product, despatched fresh rather than held in stock, and it cannot be returned.