A single national planting calendar for Uganda does not work, because the country does not have a single rainfall pattern. The south, centre, east and west receive two rainy seasons a year; much of the north receives one long one. A date that is right in Masaka can be two months wrong in Kitgum, and a calendar that averages the two is wrong everywhere.
The two patterns
Bimodal areas, covering most of the south, centre, east and west, have two growing seasons. The first runs with the rains that arrive around February to March and continue into May or June. The second runs with rains from around August or September into November or December. Two crops of a short-season cereal or legume are possible in a year, and most households take both.
Unimodal areas, covering much of the north, have one long wet season running from around April into October, with a pronounced dry period on either side. There is one main cropping season, it is longer, and a crop missed is missed for the year.
The boundary between the two is a gradient rather than a line, and districts near it behave differently from year to year. If your area sits near the transition, your own records are worth more than any published map.
Plant to the rain, not to the date
Onset dates move. A calendar that says "plant in the second week of March" is a summary of past years, not a forecast of this one, and planting dry into ground that then stays dry for three weeks is a common way to lose a seed order.
The usual rule is to plant once the rains have established rather than on the first shower: enough rain to wet the soil to planting depth, and a reasonable expectation of more within the week. Planting into a false start costs the seed and the labour, and the replant goes in later than if you had waited.
Against that, planting late in a bimodal season is its own risk, because the crop's flowering, which is the stage least able to tolerate dry soil, moves towards the end of the rains. For maize this matters more than almost anything else: see maize planting seasons in Uganda.
Count backwards from flowering
The useful way to position a planting date is to work back from the stage that cannot tolerate drought, rather than forward from the first rain.
Find how many days your variety takes to reach flowering, then count back from the point in the season when the rains are reliably still falling. Plant so that flowering lands comfortably inside the wet period rather than at its edge. A variety that matures in 90 days and one that takes 120 should not go in on the same date at the end of a season, and the shorter one is usually the right choice for a late start.
Building a calendar for your own district
The calendar worth having is the one you built from your own fields. It needs three records kept for a few seasons:
- The date the rains established each season, not the date of the first shower
- The date you planted each crop, and on which plot
- What happened: emergence, whether flowering coincided with dry weather, and the yield
After three or four seasons this tells you something no national calendar can, which is how your own ground behaves and which of your planting dates actually produced. The format is in the farm record keeping guide.
What else the calendar has to carry
Planting dates are only part of a working calendar. Weeding windows matter as much as planting dates, because the first few weeks decide the crop and they fall when the rain makes access hardest. Input purchase has to happen before the rush, when stock is available and prices are calmer. Labour peaks need to be spread, because two crops whose weeding falls in the same fortnight will both be weeded late.
Where the person-days pile up is worth mapping before the season rather than during it: see how to calculate farm labour costs.
Livestock has a calendar too
The feed year follows the same rains. The end of a dry season is when body condition is lowest and when bought feed costs most, and planning forage conservation for that window is the whole game: see animal feeds and health. Vaccination and deworming schedules run on their own clock and should be written into the same calendar: see the livestock vaccination calendar.
Frequently Asked Questions
How many planting seasons does Uganda have? It depends where you are. Most of the south, centre, east and west are bimodal, with two seasons a year: one starting around February or March, the other around August or September. Much of the north is unimodal, with one long season running from around April into October. Districts near the transition can behave like either in a given year.
Should I plant on the first rain? Usually not. A single shower can be a false start, and seed planted into ground that then dries costs you the seed and the labour and delays the replant. Wait until the rains have established, meaning the soil is wet to planting depth with more rain reasonably expected, then plant without further delay.
How do I choose a planting date for my variety? Count backwards from flowering, which is the stage least able to tolerate dry soil. Find the days your variety takes to flower, and plant so that flowering falls well inside the reliable part of the rains rather than at the end. For a late start, a shorter-maturing variety is usually the better choice.
Why can I not just use a national planting calendar? Because the country has two different rainfall patterns and a published national date is an average across both. It will be roughly right in some districts and badly wrong in others, particularly in the north, where there is one season rather than two.
What should I record to build my own calendar? Three things each season: the date the rains established, the date you planted each crop on each plot, and what the crop then did, especially whether flowering met dry weather. After three or four seasons that is a better guide to your own ground than any map.