Living Land

transplants are not scorched by any ammonia gas that may

still be emanating from the organic sources.

Spot application of organic manure is recomemmended

for crops such as lemongrass, watermelon and fruit trees

and also for those crops with spacing at 1 m x 1 m or

greater. Spot application will save the total amount of

organic sources required per hectare. The organic source

is applied in planting holes and then thoroughly mixed

with the sand before planting.

The rates of application of the organic inputs depend on

the crops to be planted. For tomatoes the yield increased

significantly with application of 70 t/ha of POME while leaf

mustard yield increased linearly when poultry manure was

applied at 10-40 t/ha. Okra and cucumber yield increased

when 40-50 t/ha of poultry manure was applied. Chilli

increased significantly when 80 t/ha POME was applied.

For leafy vegetables an application of 30-60 t/ha of poultry

manure significantly increased the yield. For short-term

leafy vegetables a basal application of about 40 t/ha of

poultry manure is sufficient.

Organic fertilizer significantly affects the yields of crops.

Applying organic matter greatly increased the yield of crops

such as sweetcorn, chlli and tomato. A combination of organic

and inorganic fertilizers greatly boosted the yields of all the

crops. Yields of leafy vegetables such as Chinese mustard,

Chinese spinach, water convolvulus, lettuce and Chinese

chives, grown on sand tailings with appropriate amounts of

organic and inorganic sources of nutrient can match or exceed

the mean yields achieved by farmers on normal soils. Several

fruit vegetables also perform well on sand tailings compared

to the mean yield of farmers working on normal soils. This

clearly shows that organic inputs supplemented by inorganic

fertilizers are crucial to high productivity. Planting herbs on

sand tailings also produced good yields. Herbs such as lemon-

grass, ginger, turmeric, noni and aloe vera produced yields

that exceed farmers’ means when planted on sand tailings.

These results indicate that problem soils such as sand

tailings can become productive farms when given proper

treatment with organic inputs. Crops such as vegetables,

fruits, sweet potato, sweetcorn and herbs can be success-

fully produced by application of the technologies developed

by MARDI. With these technologies sustainable agricul-

ture production on sand tailings is equal that obtained from

normal soils. Thus soil improvement in sand tailings has

not only produced fresh fruits, vegetables and herbs for the

nation but also helped to improve farmers’ incomes.

Sand tailing areas are close to urban areas with a ready market for

fresh food crops

Image: MARDI

Irrigation for agriculture: (left) a lake on ex-mining land provides a water source and (right) mangoes are planted on slime tailings with an irrigation trench

Images: MARDI

[

] 170

iving

and