The more I grow things the more I am surprised that so called sun plants do just fine in shade and vice versa. Some plants prefer sun and some prefer shade. The raw energy conversions are:1kWh = 3412 Btu = 3.6MJ = 859.8kcalĭo they really believe gardeners are going to do these calculations? Plants Require Sun or Shade The conversions based on surface area are: 1 kWh/m²/day = 317.1 btu/ft²/day = 3.6MJ/m²/day Warning – do not look directly at the sun. May I suggest that if you go outside 3 or 4 times during a single day, and look up, you can determine these values without a meter. The Sunlight Calculator gives one of four readings which translate into the following. So to make this work you need to go outside and turn it on before sunup. Sunlight Calculator then measure light for only part of the day, and will give you the wrong readings.

“Though not a panacea for all garden problems, it can help you locate plants where they will grow best.” Not really, since light levels are just one of the parameters to consider.Īfter you turn it on, the meter measure the amount of light for 12 hours and determines how much sun you have.

You get neither duration nor intensity readings.

It only reports sun, part sun, part shade or shade.

“This meter measures the duration and intensity of sunlight falling at a given spot over a 12-hour period.” It might measure these things but it does not report them.

“The lighting conditions of the micro-climates in your garden aren’t always obvious.” Yes they are – just hold out your hand and look for shadows.

The following are taken from the dealers ad. Sunlight Calculator, a product you don’t need

Download how much sunlight per day