Plant grow light table how to#

How Far Should LED Grow Lights be for Flowering PlantsĪs plants grow, their needs change. Depending on the power of the light and maturity of the plants, this could vary quite a bit between 14-36 inches from the top of the plant canopy. With clones, they will need intense light to begin. The LED grow light distance above the clones differs from the height required for seedlings. How Far LED Grow Lights Should be From ClonesĬannabis cloning is a process where clippings or cuttings from a mature plant are used to grow another plant of the same kind. Depending on the size of the light, it is safe to keep grow lights located somewhere between 24-36 inches from the top of the soil. This means you do not want to turn up the intensity too early as the seedlings will thrive with a far gentler approach. How Far Should LED Grow Lights be from Seedlings?Īt the very early stages of growth, seedlings are delicate and require less light intensity. Depending on lights and how you want your crop to grow, it is not necessary to change the height of the lights during flowering, especially if you do not want taller plants. It is at this stage that the plants increase in height and grow fruit. The top leaves of the canopy should be between 18-24 inches from the light source to produce flowers. During this stage, more light is needed for photosynthesis, so the light source should be located closer to the plants.Īs the plants progress through the flowering stage, their demand for intense light decreases. In the vegetative stage, LED grow lights should be between 12-24 inches away from the top of the canopy. Once roots have been established and sprouting has started, the lights can be moved closer (usually within the first 2-3 weeks). Locate your LED grow lights at the furthest distance from the seedlings (~36”) – this keeps heat and light intensity levels lower and helps prevent seedlings from drying out. Where Should Grow Lights Be Located?įor seedlings, LED grow lights should generally be mounted between 24-36 inches above the plant canopy – however, this depends on the power (wattage) of the light source. In general, grow lights should be mounted closer to the plant canopy for vegetative stages of growth and higher up (further away from) the plant canopy during the flowering stages of growth. As the light source is located closer to the canopy, the light intensity increases. Table 1 also highlights how changing the distance of the same 600 watt LED light changes the light intensity and “light footprint” or canopy coverage a plant receives. Intensity, PPFD/ PAR, and “light footprint” all change as the distance of the light from the plant canopy increases or decreases. It outlines light intensity (lux), delivers PPFD (μmol/m-2/s-1 or micromoles per square meter per second), and also shows the “light footprint” or canopy coverage. Table 1 shows how a 600W LED grow light performs at varying distances from the plant canopy. Table 1: Distance of LED Lighting from Plant Canopy (600W LED Grow Light) LED source shown here does not use a reflector to direct the light * Coverage will vary based on the grow light being used.

It is also important because lights placed too close to the canopy can cause burning, bleaching, stunted growth, or discoloration. PPFD is an important metric because it helps growers accurately measure the light intensity for photosynthesis at the canopy level.

PPFD is the measurement of the amount of light (photons) the sun “pours” onto the plants over time. As the sun pours light onto the plants, their leaves are collecting the energy. PPFD represents the light density a plant receives over time and is measured in micromoles per square meter per second (1).Ī way to visualize PPFD is to imagine the sun is “pouring” light onto the plant leaves.

PPFD (Photosynthetic Photon Flux Density) measures the amount of light (PAR) a plant receives over time. PAR (Photosynthetically Active Radiation) describes the portion of the visible spectrum that plants “see” and use for photosynthesis (400nm-700nm).

Plant grow light table how to#

It also addresses how to determine the proper distance of LED lighting from the plant canopy to nourish plant growth, as well as the importance of PPFD (PAR), and other popular grow light terminology. This article outlines the different lighting needs for a variety of plants, (including cannabis) according to their growth stage. See all available Cannabis Grow Lights by BIOS It is important to also understand how optimal grow light distance impacts the different phases of plant growth. LEDs emit less heat than HID sources which means that the proximity of LED grow lights to the canopy varies from that of traditional grow lights. Today, more growers are moving away from traditional HID and fluorescent T5 grow lights and are installing LED lighting.