Spring rainfall can quickly change the picture across established pastures. While additional moisture supports valuable feed growth, it can also encourage fresh weed germination and accelerate the development of existing weeds.

For southern pastures, there are plenty of weeds worth watching for fresh germination following spring rainfall, some including:

  1. Fleabane – Spring germination can lead to persistent plants that become increasingly difficult to control as they mature.
  2. Fat Hen – Favours warmer soils and fertile, disturbed paddocks, with rapid growth following spring rainfall.
  3. Black Nightshade – Germinates as temperatures rise, particularly in cultivated paddocks and areas with reduced pasture competition.
  4. Pigweed (Amaranthus spp.) – A fast-growing summer weed that thrives in warm conditions and can establish rapidly following rainfall.
  5. Blackberry – New seedlings can emerge during spring, while established plants produce vigorous new growth as temperatures increase.
  6. Common Sowthistle (Sow Thistle) – Can germinate throughout the year, with fresh spring emergence common following favourable rainfall.
  7. Scotch Thistle – Germinates during autumn and spring, particularly in open pastures, bare ground and disturbed areas.
  8. Wireweed (Hogweed) – A summer-growing weed that germinates as soils warm, particularly following spring rainfall in open or disturbed paddocks.

Particular attention should be given to paddocks containing mixes with clovers, chicory and plantain pasture species, as herbicide selection can be difficult once weeds become too big.

As spring moves into summer, the focus shifts from control to minimising weed impact, limiting seed set and protecting productive pasture species.

Effective control starts with correct identification and timely management.. Timing remains one of the biggest factors in effective weed control. Notman Pasture Seeds can assist you in identifying weed species, assessing its growth stages then selecting a control strategy. Sometimes depending on the species present in the pasture selective herbicide options may be limited.

Grazing, Hay & Silage – Future plan Withholding Periods: Before spraying, consider withholding periods for grazing, hay and silage. Restrictions vary between herbicides and can affect planned grazing or harvest dates.

For advice on identifying weeds and selecting suitable control options, talk to the Notman Pasture Seeds team.