LED lighting – the need to consider the whole picture

With the vast array of LED lights on the market for the horticultural industry, the modern day grower is faced with a daunting choice when determining what LED lights are the best for his or her situation.



There is no doubt that price is always a factor when choosing lights, but the cheapest price may turn out to be an expensive mistake in the long run. So although your lighting solution may appear to be a great bargain on ebay, the reality is that you may well be buying an inferior product.



Quality suppliers will offer a fairly long duration timeframe on the product in terms of expected efficiency. Timeframes of 25,000 hours of use with the underlying guarantee of the effective output of the lights not falling below 90% efficiency are commonplace with the quality end of the market.

You should also consider the services that your supplier is going to include in the price before purchasing. Whoever is ultimately destined to get your trade should be able to offer you services such as developing an effective lighting plan, advice on spectrum type and ideal micromole levels for the chosen crop type.



They should also be working with you to develop a return on investment document to provide you with a clear indication of the benefits, both in terms of potential increased financial returns and yields/production that will ultimately assist you in making the correct choice.

The larger suppliers will also want to work with you to establish a trial as a ‘proof of concept’ of their products. They are in the market for the long haul and want to build grower confidence in their products as against gaining the ‘quick buck’.



But having made your choice and purchased your lights for a trial, keep in mind that a trial of lighting on a crop will also require attention to other detail.

By giving any plant either supplementary lighting or extended day length, you are increasing the plant’s capacity to photosynthesise and generally work harder. So just turning on lights isn’t like waving a magic wand for instant results and raised profits. You will need to consider other factors within your greenhouse climate that now have to be ‘tweaked’ to complement the increased light levels that your plants are being exposed to.

Ideally your trial will be in a compartment which will allow for easy changes in parameters. However, the reality is that you may just be trailing lighting on a sample of rows. If you can’t apply additional water and nutrients to these plants then you are effectively going to expose them to a more stressful environment. This can be overcome by locating the trial within a single valve group for irrigation, or modifying the irrigation system to effect this.



With faster growth rates also comes increased CO2 uptake. Again the ideal trial will allow for an increased injection rate of CO2 to keep levels at an optimum, but practically it may not be possible to manipulate the CO2 levels in a single area of a large greenhouse.

You will also need to ensure you are comparing like with like. Ideally your plant rows that are utilising lights will be of the same type for unlit plants.

And finally, with plants transpiring more will come a potential for increased humidity levels in the greenhouse in the lit area which will need to be managed.

So is it all too hard? Well don’t forget the reason you are having the trial – to see benefit in your companies home location, and without a trial you may well invest a huge amount of money and not see any tangible benefit – so the trial serves the grower well to boost his or her confidence in the process of growing with lights.



Ultimately the addition of lighting to a crop must give a financial benefit, and this is often realised by increased production at a time of the year when other growers are struggling with lower light levels and slower growth rates, so you can get a better price for your produce, and reap the rewards.

So if you are serious about getting in to LED lighting, feel free to talk to your supplier and let them help you in your decision making process.

Tony Bundock is the product manager for Philips LED lighting with Powerplants Australia.

For more information:
Powerplants
sales@powerplants.com.au
www.powerplants.com.au