At the recently concluded Seeds of Gold Farm Clinic in Bulindi-Hoima, it turned out that farmers were more willing to try out piggery than the other enterprises such as bananas, apiary, cassava and fish.
In Masaka, with the hopes of ever being the country’s banana hub again fast dwindling, crop experts predict citrus production to be the best lucrative alternative that farmers can reap from handsomely.
According to Muzardi crop expert, Robinah Gafabusa, citrus has its origin in Southern China, Northern and East India and South East Asia. It is now universally grown in all of the six continents, in more than 100 countries. The first introductions of citrus in Uganda were in 1900. She adds that citrus is a crop of economic importance and also a valuable source of vitamin C.
Citrus grows over a wide range of soils but light, well drained (sandy) soils are most ideal. For good production citrus require well distributed rainfall or supplementary irrigation throughout the year. A good source of water is therefore essential in orange farming. Water requirements vary according to weather conditions, but as a whole the ideal range is between 450mm – 2,700mm per year. Citrus can be grown from as low as sea level to 200 metres above sea level. Areas of low humidity are most ideal.
Such a climate is important for reduced disease intensity and for acquiring good orange colour.
A dry hot day, cool at night climate favours good colour development. Citrus requires temperature ranges from 13°C and 38°C. Optimum temperature is 25°C-35°C. Extremely high temperatures may be harmful especially during flowering. Damage occurs in the form of flower and leaf drop.
Wind can also cause serious damage to orange trees and fruits. Hot dry wind will often scorch trees by drying young leaves. Winds of high speeds will scar fruits and cause fruit to drop. Where winds are a problem, wind break shelters should be planted.
There are several cultivated Citrus spp in the world but the most important ones include Citrus sinensis (sweet orange), Citrus aurantifolia, Citrus lemon, Citrus paradris (grape fruit), Citrus renticulata (tangerine).
In Uganda citrus farming is on small scale, but in the early 1960s the Uganda government tried to establish citrus in Teso, Apac and Kamuli.
Citrus can be grown in any part of Uganda and the citrus industry has a very high potential but right now we are still importing.
Although citrus can be grown from seed, budded or grafted (vegetatively propagated) seedlings are preferred to as planting material.
Propagation by seed takes a long time to produce fruits while vegetatively propagated seedlings take about two to three years.
Vegetatively propagated materials can be obtained from government/institutes or private commercial nurseries.
Citrus plants can be propagated through seed or grafting. Most citrus growers prefer the grafting method, especially the budding technique which has advantages like seedless fruit are produced, genetic uniformity, a vigorous root stock (resistant to pests and diseases or tolerance to poor soil) and they start bearing fruit earlier than the seed propagated ones.
“In Uganda, we have been using the lemon as a rootstock though Trifoliate and Cleopatra cultivars are also used worldwide because they are resistant to a number of pests and diseases, tolerant to water logging and can tolerate heavy soils unlike other oranges species,” says Gafabusa.
The time from budding to planting can vary between six months to two years. They can be transplanted as bare rooted plants or if they are arranged in sleeves, they can be transplanted with soil.
The land should be ploughed up to medium tilth and levelled if necessary. All perennial grasses such as couch grass should then be cleared and burnt or sprayed beforehand using Round-up (glyphosate) or weed master. Farmers should know that grape fruit spacing is (25 x 25) ft, sweet orange spacing is (20 x 20) ft and lime orange spacing is (15 x 15) ft.
Planting arrangement may be square or rectangular.
During planting the holes are dung 2ft deep and 2-3 ft wide. Put the top soil on one side and the sub soils on the other side, mix a tin of manure with the top soil and put the mixer in the hole.
Place the seedling in the hole and put back the sub soils up to the root collar. Young crops can be interplanted with other crops. In high rainfall areas, permanent cover crops can be interplanted and can be checked by slashing or chemicals but in drier areas where the cover crops may compete for moisture with the oranges, the soil is kept clean.
It is very essential to remove all suckers especially those which develop from the rootstock.
It is advisable to carryout leaf nutrient analysis in order to determine fertiliser requirements.
Oranges are always deficient in zinc and magnesium and these deficiencies can be controlled by spraying with ZnSO4 or MgSO4 as foliar sprays and you can incorporate other fertilisers.
During harvesting, it is very important to keep the fruits on the trees until they are fully mature but in Uganda, the colour is seldom an indicator of maturity since fruits tend to remain green.
Pests and diseases
The most common include Scales, Mealy bugs, Mites, Aphids and Leaf miness.
In Uganda, these diseases include Brown spots, Foot rot, Alternalia brown spot, Citrus scab, Citrus greening and Trestiza
Muzardi at a glance
Mukono Zonal Agricultural Research and Development Institute (Mukono ZARDI) is one of the nine public Zonal Agricultural Research and Development Institutes (ZARDIs) which were established through the NARS Act of 2005.
The institute is responsible for carrying out applied and adaptive research in the Lake Victoria Crescent Agro-ecological Zone.
It covers 21 districts of central Uganda which include: Mubende, Mityana, Luweero, Kyankwanzi, Mukono, Kayunga, Nakasongola, Nakaseke, Masaka, Kalangala, Buikwe, Kalungu, Lwengo, Mpigi, Kampala, Bukomansimbi, Gomba, Butambala, Buvuma, Wakiso and Kiboga.
15th Seeds of Gold Farm Clinic
Theme: Climate Farm Clinic
Enterprises: Coffee, bananas, apples, mangoes, citrus, livestock (pigs, cattle, goat), fish
Topics: Agribusiness, Crop/ Livestock management and health, post-harvest handling, crop and livestock species
Date: Saturday, Sept 7, 2019
Entry: Free, free lunch and breakfast