Farm tools

Know your farmBefore you commit

19 free farm tools on South African figures: Grain SA, SAFEX and the Land Bank. Pick one, type your own numbers.

Harvest date

When will my crop be ready?

1. Your crop

The day the days count from.
Count the days from
Grain SA's days count from emergence.

2. Your cultivar

Grain SA, maize: about 119 days from emergence to physiological maturity (the black layer at the base of the kernel), one example; ultra-short to long cultivars differ.
Source: Grain SA, Pula Imvula: Harvesting at the right time is vital (R. McPherson, July 2021).
Empty: Grain SA's 119 days above.
Drying to harvest, Grain SA: the kernel moisture falls from about 35% to 14% in the next 40 days or more. Harvest at below 14%.
Empty: no upper end is published, so the window stays open.

3. Heat units at the farm (optional)

Grain SA, heat units for maize: a day's heat units are (maximum + minimum) / 2 less 10 C; a cold day counts 0. The temperatures: NASA POWER daily temperature at 2 m (MERRA-2), 2001 to 2025, the average day of each month in the farm's cell of about 50 km, for 961 South African towns.
Every South African town of 1 000 people or more.
If your seed company gives them, counted the same way (base 10 C).
Decimal degrees, south negative; from the agent or your own map.

The answer

Enter the date the crop was up (emergence).

When it comes in: store or sell?Ask Africa EstateRead: Crop farms in South Africa
How this works and the sources

From the day you planted, or the day the crop came up, and your cultivar's days to physiological maturity, the date the crop is ripe; then the drying days to harvest moisture as a range: the window in which the combine can roll. Your seed company's days for your cultivar come first; where you leave them out, the crop's published South African figure is used and named (Grain SA for maize, soybeans and sunflower, Pannar for grain sorghum). Wheat has no published figure we could read, so it needs your cultivar's days. For maize, the heat units too: Grain SA's formula on NASA POWER's temperatures for the town nearest the farm, anywhere in South Africa, or the farm's own coordinates.

What this does not tell you

  • The days are counted, not the weather: a cool season makes the crop later, a hot one earlier. For maize the heat units help, but they are an average year (2001 to 2025) in a cell of about 50 km around the town or the farm, not this season and not the farm's own weather station.
  • Heat units only for maize: Grain SA gives the base temperature (10 C) for maize; for soybeans, sunflower, sorghum and wheat we have no South African base temperature, so they count days only.
  • A frost before maturity ends the season early; sorghum is very sensitive to it.
  • Grain SA's 119 days for maize is one example; ultra-short to long cultivars differ by weeks. Enter your cultivar's days from the seed company.
  • The harvest window is a range, not a date: the moisture of the grain on your lands and the limit of your silo decide. Walk the lands and test before you plan the combine.
  • No agronomic advice: speak to your seed company or your adviser.
  • Nothing you enter is uploaded or kept by us; the share link carries the crop, the date, the days, the town or the coordinates you typed and the heat units only. The towns and temperatures are read from our own site.

Sources

Estimate, not advice. Confirm every figure with your bank, attorney and tax practitioner before a decision.