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Wildflowers WANT poor soil: strip the turf and the top few cm of fertile topsoil first, or the grasses and nettles win. Don't fertilise, ever. Mix seed with dry sand (1:4) to sow such small amounts evenly, tread it in (don't bury), and add yellow rattle in autumn: it's semi-parasitic on grass and is the meadow-maker's secret weapon. Then the hard part: one cut in late summer, cuttings REMOVED, and otherwise leave it alone.
What The Wildflower Meadow Calculator Works Out
- Seed needed: area x the sowing rate, rounded up to the gram. Pure wildflower mixes go down at 3 g to 5 g per m2 and 80/20 flower-and-grass meadow mixes at 4 g to 6 g, so a 20 m2 lawn corner wants about 80 g, a quantity that vanishes in a cupped hand.
- Rough cost: specialist native-provenance seed runs 8p to 15p a gram, which is the range shown. Generic "bee mix" is cheaper but the serious end of the trade regards it the way bakers regard cake mix.
- The counter-intuitive rule: wildflowers evolved for thin, hungry ground and lose every fertile-soil contest to grasses, docks and nettles. Deliberate poverty, never fertilising, is the single biggest predictor of flowers rather than a rank sward.
- The calendar: sow in late March to April or, better, September onto bare, raked and firmed soil. Year one is cornfield annuals; the perennial community that is the real meadow arrives in years two and three.
- Custom sowing rate and seed price (advanced): use the rate printed on your supplier's bag and their actual price per gram. Cornfield annual mixes often go on at 2 g to 3 g per m2; a few premium mixes are quoted at 1.5 g.
- Yellow rattle (advanced): the meadow-maker's cheat, a semi-parasitic annual that feeds on grass roots and suppresses exactly the competition the flowers need suppressed. Sow 0.5 g to 1 g per m2 of fresh seed in autumn; it costs more per gram than the main mix, typically 15p to 30p.
- Sand to mix in (advanced): seed is bulked with dry sand, usually one part seed to four parts sand by weight, so the broadcast is visible and even. Split the mix in two and sow in two passes at right angles.
- Topsoil to remove (advanced): area x stripping depth gives the volume, at roughly 1.5 tonnes per m3 of topsoil. Stripping 5 cm to 10 cm off a lawn is the standard preparation; the card prices disposal at your skip or grab-lorry rate per tonne (a 6-yard skip holds about 4.5 m3).
- Mowing time saved (advanced): the hours a push mower would have spent on this patch at 26 cuts a year, replaced by a single late-July or August cut after seed has set, with the cuttings removed without exception because left clippings are fertiliser and fertiliser is the enemy.