Root Awakening (24 Oct 09)

The last instalment for the Root Awakening column for October 2009 was published yesterday. The first question of the usual three asked about the care of cacti in the tropics. Cacti, in general, are sun-loving plants that require a location with direct sunshine to grow well. If one are growing them in an apartment, place your cacti either on a sunny windowsill or corridor. Make sure they get some direct sunshine for at least 4 hours daily.

These plants are also drought-tolerant and they need to be potted up in a very well-draining, gritty, soil mix, for example, one that consists of 1 part of commercial houseplant potting soil mixed in evenly with 1 part of good quality, sifted burnt earth and broken charcoal chips. Use our index finger to test for soil moisture below the surface before watering each time. Cacti do benefit if their root zone dries out a little before the next watering.

The second question was about the yellowing of leaves in a passion fruit vine. Yellowing of leaves may point towards a lack of nutrients essential for growth. However, if a plant is well-fed, the loss of lower leaves may mean that a passion fruit plant is suffering from a lack of water. A large plant grown in a pot would require more frequent watering. One may want to consider to transplant the vine into a larger pot and also lay a layer of organic compost on the soil surface to help conserve moisture. Note that the passion fruit vine needs to be exposed to at least 6 hours of direct sunshine for it to flower and fruit.

The last question dealt with the growing of the cooking ginger. The leaves of the cooking ginger turned yellow and dry because its growing environment is excessively hot and this is commonly experienced by high-rise apartment gardeners. Hence, it would be beneficial if you can relocate the plant to a semi-shaded site. It should also be protected from excessive wind which can cause your plant to dry out. Grow your ginger plant in moist, fertile and well-draining soil. Rhizome rot is likely to occur if a plant is grown in heavy clay soil that is constantly wet.