There are three main categories of strawberry plants; june-bearing, everbearing and day-neutral. June-bearing strawberries bloom when daylight is limited in the short days of spring , and produce one harvest of fruit per year during a short period in late spring to early summer . Everbearing strawberries initiate flowering when the day length is 12 or more hours per day, and generally produce 2 to 3 harvests per year, distributed between early spring and late fall . Day-neutral strawberries on the other hand are not sensitive to day length and therefore do not require a certain day length to set fruit. Day-neutral strawberry plants usually produce fruit continually throughout the whole season, from July to October.
Strawberry plants generally thrive under moderately high light conditions, with light intensities ranging from 300 to 450 μmol/m²/s depending on photoperiod and cultivar. Ideal growth temperature also varies with the strawberry type, but generally daytime temperatures should be kept below 25℃ to avoid suppression of flowering and plant stress, and night temperatures should be considerably lower in order for the plant to produce high quality fruits. Light quality is another crucial factor in strawberry cultivation. A full spectrum with an additional portion of far-red light promotes a favourable morphology and increases yield on many strawberry varieties, although responses can vary between cultivars.
Using a LED lighting system instead of HPS comes with a number of benefits, not least related to heat management. Since strawberries perform best under relative high light intensities but at the same are sensitive to high temperatures, the greatly heat radiant HPS lights may not be able to meet both of these requirements. LED lights on the other hand can produce the desired light intensities while maintaining a low heat output, which makes the optimal climate easier to achieve and control, without excessive HVAC costs.
