Daily Archives: November 14, 2009

Root Awakening (14 Nov 09)

In this week’s Root Awakening column, answers to three gardening questions from Straits Times Life! readers were given.

The first question was about why the flower buds of a hibiscus plant turned yellow and fall off before they blossom. Inadequate or excess watering a hibiscus can cause it to abort flower buds prematurely. It is necessary to ensure the roots are kept moist at all times during hot and dry weather. There may be a need to increase the rate of watering as well as lay a layer of compost as a mulch which can help to keep roots cool and reduce rate of evaporation.

If it is a case of excess watering, check whether your plant is potted in a well draining soil mix. One may want to incorporate some good quality burnt earth into the soil mix to increase porosity. Hibiscus plants, in general, do not tolerate prolonged wet feet. It could be due to lack of nutrients such as like phosphorus and potassium. Consider supplementing plants with a water-soluble fertiliser such as Gaviota or Phostrogen.

The next questions dealt with composting. Burying of vegetable and fruit scraps in the ground usually involves anaerobic composting and this process requires 3 to 6 months to complete, depending on a myriad of factors and environmental conditions. Kitchen waste consisting of fruit peels and vegetable scraps are termed as ‘green’ materials. Remember to add in ‘browns’ such as dried leaves into your compost pile to ensure a healthy carbon:nitrogen ratio. All materials added to the pile should be shredded into fine bits to hasten the process.

The last question was about the appearance of mushrooms in the soil. Mushrooms are fungi that sometimes emerge from moist soil that is rich in organic matter that already has some spores in it. Such fungi usually do not do much harm to your plants most of the time. One may sometimes consider changing the soil but do note that this may not be able to remove all traces of spores and fungal mycelia. Alternatively, do try to drench the soil of the affected potted plant with fungicide such as Captan to reduce the incidence of fungal emergence.