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When it comes to ensuring optimised plant growth, quality and yield, there is one thing that will always be top of mind for the grower – light.

Which is why there are multiple important horticultural metrics that have to be understood, managed and controlled to ensure healthy plants and an optimal return on investment.

These metrics are invaluable in transforming any grow space into one that fully realises its potential, and while they can be complex when you dig below the surface, they are easy to understand and implement. This list of the most important horticultural metrics will give you an immediate and relevant overview that you can use to optimise and transform your space.

Photosynthetic Photon Flux – PPF

PPF is the term used to define the total amount of photosynthetic active photons that are emitted by a light source, per second, and they are measured in μmol/s. PPF is immensely valuable to the grower as it can help you to determine exactly how efficient your lighting is, how well it is converting electrical energy into photons of PAR, and how much of this light is landing on your plants. It is: ‘the number of photons in the 400-700nm waveband incident per unit time on a unit surface’.

Photon Efficacy – PPF/W

Also an integral part of plant growth cycle, yield and health, PPF/W is measured in μmol/J and it determines how well your lighting system is converting electrical energy into photons. As explained in a recent article in GPN Mag: ‘the appropriate metric for plant lighting is photosynthetic photon efficiency. The theoretical maximum PPE for LEDs is 4.6 to 5.1 μmol/J-1, depending on the composition of the LEDs used in an array.”

Photosynthetic Photon Flux Density – PPFD

Measured by μmol/m2/s, photosynthetic photon flux density or PPFD establishes exactly now many photosynthetically active photons are landing on a particular surface at any given moment. It is: ‘the number of photons in the 400-700nm waveband incident per unit time on a unit surface.’

Day Light Integral – DLI

The DLI is defined as the cumulative amount of the total number of photons that land on a particular surface during the daily photoperiod and is measured in mol/m2/d. It is: ‘is the amount of PAR received each day as a function of light intensity and duration.’ DLI plays a pivotal role in plant growth, yield and development, and it can be carefully managed and controlled in variable conditions to ensure that you get the best possible results.

So, the next question you probably have is – how can I integrate and manage these critical horticultural metrics into my own grow space?

The answer is to work with a company that has an in-depth understanding of lights, particularly LED grow lights, and horticultural metrics and knows how to apply these to your unique situation.

Light Science Technologies has a laboratory, the technology, the expertise and the experience to support you in achieving the right results.