Curcuma bulbs should be planted in a well drained planting medium and the soil may be mixed with
coconut husk, peat, rice husk and coarse sand to achieve better drainage qualities.
Do not plant the bulbs too deep. 1.5cm to 3cm soil on top of the bulbs is sufficient.
As Curcuma bulbs usually start to sprout during April in Thailand when temperatures are rising
and sunlight intensifies a recommendable time for planting would be March to April.
Larger Curcumas like Curcuma alismatifolia ‘Pink’ and the other C.alismatifolia varieties
should be planted 25cm to 30 cm apart to provide sufficient space.
When planting in an open field a distance of 1.20 to 1.40m between rows is recommended.
If using pots the diameter should be about 30cm ( 12 inches ) and the pot should be
also 30 cm ( 12 inches ) high.
Smaller Curcumas like Curcuma thorelii ’Chiang Mai Snow’ can be planted in smaller pots. Up to 3 bulbs
can be planted into 1 pot, provided the distance between bulbs is about 20cm.
Using this method will produce showy container plants in less time.
Upon planting 1 tablespoon of Fertilizer 15:15:15 or 16:16:16 can be applied for the larger Curcuma species and varieties. For smaller varieties less fertilizer is required.
After planting water thoroughly. Then let the soil dry until it is still moist but not wet and keep evenly moist by watering daily.
For already growing plants fertilizer can be applied monthly using the same ratio of 15:15:15 or 16:16:16 .
About 1 flat teaspoon for smaller Curcuma and a little more for the larger Curcumas should be sufficient.
However this depends also on temperatures and general growing conditions.
Over fertilizing with Nitrogen can cause weak stems and low flower production.
For Curcuma alismatifolia varieties it will take about 1 to 4 months after planting until the plant blooms, depending on the quality of the bulbs.
During the first year one plant may produce 3 to 5 inflorescences.
In Thailand the bulbs are dug out every 2 years. They will then be divided and replanted, often in a different location
to avoid disease.
Curcuma will grow well if the soil is kept evenly moist and for this mulching is very helpful. Also the plants may be watered daily during hot weather.
However, heavy sprinkling can cause damage to the flowers and should be done with care.