Divisi
When to plant Irish potato in Rubirizi
Western, Uganda
Known here as viazi mviringo · kiazi
The Irish potato (mbatatisi, ikirayi, viazi mviringo) is a cool-weather crop grown for the tubers that swell underground — it is not a grain, and it is not the same plant as sweet potato.
| Measure | Rain-fed | With irrigation |
|---|---|---|
| Fit | Favourable | |
| When to plant | 30 Sep 2026 – 30 Oct 2026 open now | 2 Mar 2027 – 30 Jun 2027 |
| Expected harvest | about 30.4 t/ha | about 40.3 t/ha |
| Harvest | From 9 Dec 2026 to 9 Mar 2027, depending on the planting date | |
| Ready to harvest | 70–130 days after planting | |
| Work it takes | 110–185 days per hectare, by hand | |
| Rain meets its needs | 97% | |
Rain-fed. These dates are worked out from each place's own rainfall, for a field watered by the season — with irrigation a window can open earlier, close later, or come round more than once a year. Check your own field under What grows, or get the Divisi app for a calendar dated to your farm.
If you only get one chance to plant, aim for around 15 Oct 2026. That is the point in the window where the rains are most reliably established.
This season's outlook for Rubirizi leans wet. Plant at the early end of the window, and make sure water can drain off the field — a wet year does more damage through waterlogging than through the rain itself.
Planting after 30 Oct 2026 leaves the crop short of season: it runs into the dry months before it has finished filling.
What decides this in Rubirizi
| Rain and temperature | 96% |
|---|---|
| The soil | 96% |
| The lie of the land | 60% |
For irish potato in Rubirizi, the lie of the land is the tightest of the three at 60%. You cannot flatten it, but you can farm it: plant along the contour rather than up and down, ridge or tie ridges to hold water on the slope, and expect shallower rooting than the crop would manage on flat ground.
The 2026/27 season in Rubirizi
| Rainy seasons | Two each year — two chances to plant |
|---|---|
| When the rains are expected | August 2026 to January 2027 |
| Rain in a typical year | About 779 mm |
| This season's rain | Leaning wet — January, February, November and December look heavier than usual. Make sure water can drain off the field; a wet year does more damage through waterlogging and disease than through the rain itself. |
| This season's heat | Hotter than usual — about +1.1 °C over the growing months. Heat makes the same rain do less, so a dry spell bites sooner: do not plant late, and shade or mulch what you can. |
| What that supports | enough rain for one full main crop, warm all year, so nothing but rain ends the season |
| Ground this covers | 3 kinds of ground. The season below is the largest that farms — about 50% of this area. |
| 50% | enough rain for one full main crop; warm all year, so nothing but rain ends the season 262 growing days · about 760 mm · August to January |
|---|---|
| 28% | enough rain for a long crop, or two in a year; warm all year, so nothing but rain ends the season 275 growing days · about 820 mm · July to January |
| 20% | enough rain for a long crop, or two in a year; warm all year, so nothing but rain ends the season 328 growing days · about 1,010 mm · July to June |
last updated 17 September 2026
What irish potato needs to grow here
| Soil it likes | well-drained loam or sandy loam soil |
|---|---|
| Soil sourness (pH) | Happiest between pH 5.0 and 6.5 |
| Spacing | 75 cm between rows, 28 cm between plants |
| Feed it most with | potassium and magnesium |
What it takes to grow irish potato in Rubirizi
| Planting material | About 47,000 plants per hectare |
|---|---|
| Nitrogen (N) | About 100 kg per hectare |
| Phosphate (P₂O₅) | About 30 kg per hectare |
| Potash (K₂O) | About 176 kg per hectare |
| In the shops | A basal compound at planting — Compound D, or an NPK blend — covers the phosphate and potash. A nitrogen top dressing — urea or AN — goes on once the crop is established. |
| Hand work | 110–185 days per hectare, by hand |
These are the nutrients a irish potato crop of that size carries off the field. What you actually apply depends on what your soil already holds — which is what a soil test, or the app's field records, tell you.
What to watch for
Grow Irish potato with a plan, not a guess
Everything above describes Rubirizi as a whole — your own soil, slope and rainfall will shift the dates. The Divisi app works them out for your field, and dates each job that follows.
Where to sell Irish potato nearby
Irish potato in nearby districts
This calendar moves
Planting windows shift with the forecast. Leave your email and we'll send what changed, and a note when planting time nears — a couple of emails a month at most.
Frequently asked questions
Will irish potato grow well in Rubirizi?
Rubirizi rates as favourable for irish potato.
When should I plant irish potato in Rubirizi?
Typically 30 Sep 2026 to 30 Oct 2026, forecast-adjusted.
Is this exact for my own field?
No — these are readings taken across Rubirizi, not on your field. Soil, slope and rainfall change from one farm to the next. Check your own location to see your own numbers.
