crop nutrition advice
crop nutrition advice
All information about banana fertilisation, best practice, suitable products, field trials, and more can be found here.
Advice for growing banana (Musa spp.)
Bananas grow well in a wide range of soils.
Soil pH should be between 5.5 and 6.5, and soils must not be compacted.
Optimum temperature for leaf emergence is about 25-30⁰C. Banana crops are sensitive to low temperatures.
In tropical environments, a crop cycle may be as short as seven months.
Below 10⁰C chilling occurs, and irreversible frost damage happens when leaves are exposed to -2⁰C for 10-15 minutes.
Estimated nutrient uptake (kg/t):
50 ton/ha fresh fruit @ 2000 plants/ha
Source: IPI Bulletin 7 – Fertilizing for High Yield – Banana (1989).
Dynamics of banana nutrient uptake over a crop season
(kg/ha) 40 t ff*
(kg/ha) 40 t ff*
* ff = fresh fruit
Source: Research Data INIAP-IPI (2020)
Role of nutrients
|Total Soluble Solids||+||+|
|Ascorbic Acid (Vit D)||+|
+ = improving; – = decreasing;
Source: Banana Crop Guide, Haifa.
|Nitrogen||Deficiency symptoms appear rapidly and simultaneously show on leaves of all ages.
Leaves become very small and are pale green.
Mid-rib, petioles, and leaf sheaths become reddish pink, leaves production rate is markedly decreased. Distance between successive leaves is reduced, producing a 'rosette appearance’, and poor growth leading to a stunted plant. Fruit bunches become small, with a reduced number of bunches.
Reference: Rahul Mane B.Sc.
|Phosphorous||Phosphorous deficiency leads to reduced vigour, stunted growth and poor root development. Leaf margins of the oldest 4-5 leaves become chlorotic. Under severe P deficiency leaves develop purple-brown flecks eventually producing 'saw-teeth' necrosis of the leaf edges. Affected leaves curl and petioles break, young leaves have a deep bluish-green colour. Delayed fruit maturity|
|Potassium||Potassium deficiency symptoms normally appear at flowering time.
Rapid appearance of orange/yellow colour on older leaves which subsequently get dry and die. The mid-rib of these leaves is very often bent or broken at two-thirds of its length making the leaf point downwards.
Plants produce small leaves, delayed flowering, with reduced bunch size. These symptoms show before the effect on plant growth.
|Calcium||Symptoms appear on the younger leaves due to low calcium mobility into the plant, generally after a flush of growth, or as a result of unbalanced potassium application.
Interveinal chlorosis near leaf margins. ‘Spike leaf’ deformation or absence of leaf blade, fruit cracks easily upon fruit maturation, fruit bends up, producing a more concave form. Reduced fruit diameter and biomass.
|Magnesium||Chlorosis of leaf margins of older leaves. Yellowing extends towards the mid-rib, with a green band remaining near the mid-rib. The chlorosis is more severe in leaves exposed directly to sunlight, purple mottling of the petioles.
Separation of leaf-sheath from the pseudo-stem. Reduced plant height, fruits do not ripen well and become tasteless.
|Sulphur||Symptoms are similar to nitrogen deficiency, but chlorosis is uniform and general throughout the entire plant, including younger leaves. Heart leaf becomes white, and other leaf blades become very soft and tear easily. Thickening and leaf creasing, plants with advanced deficiency will be stunted.|
Recommendations for growing bananas
Step 1: Seedlings
Seedlings can be obtained from nurseries producing reputable micropropagated seedlings or self-produced by experienced fruit growers.
Step 2: Planting
To have standard plots and easier crop management, seedlings must be separated accordingly. In holes where the seedlings didn’t germinate, new seedlings can be planted 30 to 40 days after planting.
Step 3: Crop management
- Weed control should be carried out, especially in the initial phases.
- Thinning aims to eliminate excess shoots in the clump, leaving one daughter per plant and, later, the granddaughter. Each clump will usually have three plants: mother, daughter and granddaughter.
- Defoliation eliminates broken, dry, disease-infected leaves, and even those that are causing damage to the bunch. It improves shoot development, reduces disease incidence, increases aeration and luminosity, and facilitates harvesting.
Step 4: Eliminate heart and flowers
The “heart” of a banana must be eliminated 10 to 20 cm below the last lot soon after opening. This speeds up development of the bunch, improves fruit quality and reduces pest incidence. Flowers must be eliminated soon after the elimination of the “heart” and carried out only in varieties with persistent male flowers below the last bunch to also reduce pest incidence.
Step 5: Bag the bunch
This operation protects fruits against pests, physical damage, and accelerates and evens out bunch development. It must be done after removing the “heart”, male flowers, and the last bunch.
Fertiliser applications must be done depending on crop stage and based on soil contents, nutrient extraction, and weather conditions.
For the different countries, fertiliser application may vary from 4 to 24 times per year according to wet periods or irrigation frequency. However, when using slow or gradual release fertilisers the number of applications can be reduced and a positive impact on yield, quality, and profitability should be expected.
As a medium rate to obtain medium to high production an approximate recommendation would be around 400-60-600-130-60-60 kg/ha/year of N, P2O5, K2O, CaO, MgO, and S respectively, plus a reasonable rate of micronutrients based on the yield levels of each farm.