Reversing Day and Night, Rosemary, Bay Laurel Problems
Question from: Jan
Posted on: March 31, 2011

A question....with the new Hydro smart meters and the hours of high and low rates I was wondering if it would make any difference to my herb plants that are under lights, to have them on overnight and off during the day.

There is only one problem with reversing day and night for your under-light plants and that is the temperature. Day temperature should be about 5-10 degrees Celsius higher than the night temperature. It may be not much problem in the winter, but in the summer it may be hard to get a cool "night" temperature.

Also my rosemary plants have a white powder on some of the leaves and some of the bay laurels have what appears to be a stickness on some of the leaves almost like sap. Is there anything you would suggest and does this make the plants inedible.

You might have false spider mites on your plants. You need a hand-lens to see them since they are about 10 times smaller than ordinary spider mites- the latter spin webs and so give their presence away quickly. It does not make the plants inedible. Swish them in cold water once a day for about a week. If that does not stop it, spray with neem oil (2 teaspoons per litre of water plus 1 teaspoon of dishwash detergent), three times once per week. To use the plants just wash them in soapy water.

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