When to plant Watercress in Perth

Nasturtium officinale

Watercress
Watercress · Nasturtium officinale

A hardy perennial leafy vegetable for containers of compost kept constantly wet with clean water. It grows best in cool conditions and light shade. Keep home-grown edible watercress separate from natural ponds and streams where water may be contaminated by livestock or wildlife.

20 cm · Partial Shade · High Water

Calibrated to Perth · last frost ≈ 9 May

Sow indoors April to May, plant out May to July, harvest May to December. Frost risk October to May.
ActivityJanuaryFebruaryMarchAprilMayJuneJulyAugustSeptemberOctoberNovemberDecember
Sow indoorsNoNoNoYesYesNoNoNoNoNoNoNo
Plant outNoNoNoNoYesYesYesNoNoNoNoNo
HarvestNoNoNoNoYesYesYesYesYesYesYesYes

Growing guide

What to do through the growing season

  1. 01

    Sow Seeds

    4 Apr to 16 May Optional · repeat every 3 weeks

    Sow seeds around 4th April - 16th May on the surface of moist compost in small pots or modules, then press them in lightly rather than burying them. Keep the compost constantly damp while they germinate, and sow a fresh batch every 21 days for a steady supply.

  2. 02

    Thin Seedlings

    2 May to 20 Jun Dates as each sowing reaches this stage

    When seedlings are large enough to handle, from 2nd May, thin them so the strongest plants have room to spread. Keep the soil wet at all times, because even brief drying checks growth.

  3. 03

    Transplant

    9 May to 11 Jul

    Move seedlings to their final container around 9th May - 11th July, spacing them apart in wet compost standing in shallow clean water. Water in thoroughly, keep the compost constantly wet, and refresh the standing water regularly. Do not use untreated water from streams or livestock ponds for edible leaves.

  4. 04

    Feed Plants

    9 May to 9 Oct Dates as each sowing reaches this stage Optional · repeat every 2 weeks

    From 9th May, give a very light liquid feed every 14 days only if growth slows. Avoid strong feeding that makes leaves coarse, remove weeds promptly, and keep the container topped up with clean water.

  5. 05

    Harvest Leaves

    23 May to 26 Dec Dates as each sowing reaches this stage

    Start cutting from 23rd May when plants are well rooted and the shoots are leafy. Pick little and often through to 26th December, taking the outer stems first and leaving the centre to regrow.

Watercress guides by town

See how Watercress timing shifts in other towns with different frost dates.