Search for tomato-potato psyllid and most of what comes back is written by someone with a product to sell. That's not a conspiracy, it's just how gardening retail works, but it means the actual evidence for what controls TPP gets mixed in with marketing copy for whatever's on the shelf this month. This is an attempt to separate the two, plant by plant, method by method, since this site has no spray to sell you.
Mesh exclusion is the strongest evidence-backed option going, and it's not close. A 2015 study in the New Zealand Journal of Crop and Horticultural Science tested mesh crop covers specifically against TPP and found that mesh with a pore size under about 0.55mm on its shortest edge reliably kept adult psyllids out, physically, before they ever got the chance to lay an egg. That's a genuine, peer-reviewed, New Zealand-specific result, not a marketing claim. The trade-off is real too: fine mesh also blocks pollinators, so it needs to come off once a tomato is flowering and needs bees, or you're hand-pollinating instead.
Mesh exclusion is the strongest evidence-backed option going, and it's not close.
Tamarixia triozae, a tiny parasitic wasp that specifically targets psyllid nymphs, is a genuinely different category from anything in a spray bottle: a living biocontrol agent, EPA-approved for release in New Zealand since 2016, and actually sold to home gardeners by Bioforce. It's covered in more depth in this site's dedicated article, since it deserves one on its own; the short version is that it's real, it works, and it's one of the few TPP controls actually independent of buying a chemical.
Insecticidal soap and horticultural oils genuinely work on young, soft-bodied nymphs, breaking down their protective coating on direct contact, which is a real, well-understood mechanism rather than a marketing claim. The catch is coverage: soap only kills what it directly touches, so the undersides of leaves, where nymphs actually sit, need to be sprayed as thoroughly as the tops, and eggs are unaffected regardless, so one application is never the end of it.
Sticky traps, usually yellow, are worth having but are honestly a monitoring tool more than a control one. They tell you psyllids are active in your garden and roughly how many, which is genuinely useful for timing everything else on this list, but the number of adults an home garden's worth of traps actually catches is a small fraction of the population moving through your tomatoes.
Then there's the long list of branded "psyllid spray" products lining garden centre shelves, and this is where honesty gets harder, because many of them are pyrethrum or a synthetic pyrethroid at a markup, repackaged with psyllid-specific branding and a higher price than the generic version of the same active ingredient. That doesn't make them useless, pyrethrum-based products do have real insecticidal activity, it means the "psyllid" on the label is doing more marketing work than chemistry work, and a cheaper, more generic product with the same active ingredient will do the same job.
The realistic combination for a home garden is mesh while plants are small and not yet flowering, Tamarixia release once psyllids show up, insecticidal soap for anything mesh missed, and sticky traps to know when to actually look closely. None of that requires the specific bottle with "psyllid" printed on the front in orange letters.
Catching an infestation in its first week, before nymphs have built up and before honeydew has started coating leaves, is the single biggest factor in how much work any of this takes. This site's premium check-ins are timed to a tomato's actual growth stage specifically so that window doesn't get missed, rather than being noticed only once the damage is already visible.