The last instalment of the Root Awakening column for the month of September was published last Saturday. As usual, answers to three gardening questions were given.
The first question was about brown leaf tips seen on pandan plants. It is important to note that the pandan is a plant that thrives in a moist and cool area with filtered sunshine. It is a highly adaptable plant that can also grow in shade but definitely not under direct sun.
The symptoms described seem to suggest that the pandan plant was probably growing in an area that is too hot for the rest of the day since it was said to be growing under a glass trellis which can potentially trap heat from the sun. Soil that is dry can also cause similar problems. Try to keep soil moist at all times and a layer of compost serving as a mulch can also help to keep the roots cool and reduce rate of evaporation of the soil.
The second question asked about the identity of a plant that was given in the picture published in the column. The plant shown is an Indian borage, botanically known as Plectranthus amboinicus. It is a medicinal herb that is used as a cough remedy and is also commonly mistakened to be a mint.
The last question was about a rose plant and why its buds and leaves turned black shortly it was brought back home from the nursery. The rose plant in question might have been affected by thrips or spider mites that commonly attack young growth and new flower buds of rose plants.
To eradicate these pests, Condifor (active ingredient is imidacloprid), which is a systemic pesticide has been found to be particularly effective. Before spraying, it is best to prune away affected parts so as to reduce the population of pests.
Rose likes to be grown in a sunny area with moist, well-draining, fertile soil that is supplemented with organic matter such as compost. You can fertilise plants with a suitable rose fertilizer or water-soluble ones like Gaviota and Phostrogen, made up according to the manufacturers’ instructions.
Heat can be a serious problem with roses during the hot season where new shoots and buds can dry up as a result. Grow in pots so that it is easier to move plants to semi-shaded areas during that time.