Divisi
When to plant Sweet potato in Kirinyaga Central
Kirinyaga, Kenya
Known here as kiazi kitamu · viazi vitamu
Sweet potato is a trailing vine you grow from vine cuttings (slips), not from seed and not by planting the root.
| Measure | Rain-fed | With irrigation |
|---|---|---|
| Fit | Favourable | |
| When to plant | 31 Jan 2027 – 24 Feb 2027 opens in 17 weeks | 1 Jan 2026 – 30 Sep 2026 |
| Expected harvest | about 19.9 t/ha | same |
| Harvest | From 1 May 2027 to 24 Jul 2027, depending on the planting date | |
| Ready to harvest | 90–150 days after planting | |
| Work it takes | 70–148 days per hectare, by hand | |
| Rain meets its needs | 91% | |
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 12 Feb 2027. That is the point in the window where the rains are most reliably established.
This season's outlook for Kirinyaga Central 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 24 Feb 2027 leaves the crop short of season: it runs into the dry months before it has finished filling.
What decides this in Kirinyaga Central
| Rain and temperature | 96% |
|---|---|
| The soil | 76% |
| The lie of the land | 76% |
For sweet potato in Kirinyaga Central, the soil is the tightest of the three at 76%. This is the one you can actually move. Lime raises a sour soil, manure and compost lift what it holds, and both work within a season or two — money spent here changes the answer.
The 2026 season in Kirinyaga Central
| When the rains are expected | December 2026 to December 2026 |
|---|---|
| Rain in a typical year | About 1,723 mm |
| This season's rain | Leaning wet — 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 +1.0 °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 a long crop, or two in a year, warm all year, so nothing but rain ends the season |
| Ground this covers | 4 kinds of ground. The season below is the largest that farms — about 28% of this area. |
| 28% | enough rain for a long crop, or two in a year; warm all year, so nothing but rain ends the season 354 growing days · about 1,600 mm · February to January |
|---|---|
| 16% | enough rain for one full main crop; warm all year, so nothing but rain ends the season 251 growing days · about 1,120 mm · February to June |
| 16% | enough rain for a long crop, or two in a year; warm all year, so nothing but rain ends the season 365 growing days · about 1,690 mm · January to December |
| 12% | enough rain for a long crop, or two in a year; cold for much of the year, with a short planting season 365 growing days · about 1,860 mm · January to December |
last updated 30 September 2026
Frost and pest pressure hold back about 15% of yield here.
What sweet potato needs to grow here
| Soil it likes | well-drained sandy, sandy loam or loam soil |
|---|---|
| Soil sourness (pH) | Happiest between pH 5.0 and 6.5 |
| Rain it needs | About 750–1,000 mm across the season |
| Spacing | 100 cm between rows, 30 cm between plants |
| Feed it most with | potassium and nitrogen |
What it takes to grow sweet potato in Kirinyaga Central
| Planting material | About 33,000 plants per hectare |
|---|---|
| Nitrogen (N) | About 80 kg per hectare |
| Phosphate (P₂O₅) | About 30 kg per hectare |
| Potash (K₂O) | About 159 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 | 70–148 days per hectare, by hand |
These are the nutrients a sweet 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 Sweet potato with a plan, not a guess
Everything above describes Kirinyaga Central 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.
Sweet 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 sweet potato grow well in Kirinyaga Central?
Kirinyaga Central rates as favourable for sweet potato.
When should I plant sweet potato in Kirinyaga Central?
Typically 31 Jan 2027 to 24 Feb 2027, forecast-adjusted.
Is this exact for my own field?
No — these are readings taken across Kirinyaga Central, not on your field. Soil, slope and rainfall change from one farm to the next. Check your own location to see your own numbers.
