• Forums
  • QA
  • awesome product but I have some beginner questions...

awesome product but I have some beginner questions...

Nov 21, 2020 - 4:14 PM

  • Hi,

    I recently purchased a grow light from you and I’m not sure exactly how to use it.

    How far is it supposed to be from the plants?
    And what are the 2 switches on the top? Clearly, they turn on the lights, but I’m wondering what the settings/specs are for the different light emitted from each one.

    If there is a manual I could download online, a link would be great.


  • Hello! We're sorry that we haven't been clearer with this information.

    Plants will grow in a certain way depending on what spectrum they are receiving. This is called photomorphogenesis. When plants receive a dominant red light, they will grow tall. When plants receive a dominant blue light, they grow more compact and with a shorter distance between nodes (branches).
    Some growers prefer to use a dominant blue light during the seedling and vegetative phase to keep plants more compact and focusing on foliar growth rather than stem elongation.

    What is more important than spectral quality, is intensity. No matter what spectrum we are growing with, if the light intensity is lacking, plants will grow tall and stretchy either way as they are reaching for the light source. As I'm sure you know already, household lamps that are made for human use have the spectrum rated in kelvin. A high kelvin means it has a lot of blue (cold appearance) and a low kelvin means it has a lot of red (warm glow). Sunlight in the middle of the day is around 5000-6000k and if we compare that to a classic HPS bulb which is 2200k, that makes a very big difference. In theory, plants would become stretched and lanky, but since HPS puts out high intensities, it still grows well. Many professional growers today still use HPS and think it is a good lamp that produces good results, but plants will also grow well outdoors in sunlight that has a kelvin rating of over 5000k.

    The take-home here is that spectrum matters, but light intensity is far more important. A high intensity 2200k/red light will produce shorter plants than a 5000k/blue spectrum that is not strong enough.
    If the 2200k and 5000k spectrums are both the same intensity, the 5000k spectrum will produce a bit more compact plants with more foliage growth and shorter stem.

    Our lamp is designed to put out a balanced spectrum with both buttons activated at the same time. This balanced spectrum can be used from seed to harvest, but some growers still want to use an extra blue spectrum in the first week(s), which is why we split the spectrum in half. Although, most growers (including us) use both buttons activated at all times.

    Light intensity is regulated with distance and your plants will experience different intensities depending on what height you hang your lamp at. We've made detailed intensity maps (PPFD-maps) that also have some general recommendations for high-light plants.

    Here's the spectrum report for out Z5 grow light with all three settings. It shows what spectrum it puts out when having the blue, the red, or both buttons activated:

    I'm also attaching the PPFD map below. It shows how the Z5 perform at three different heights in a 3x3' reflective space:

    We know light can be tricky to understand and that it's a lot of information to take in. If you share some more information about your plants and grow space, I can help you figure out what height to hang the lamp at for optimal intensity and coverage.

  • Excellent information, thank you! What height should I hang it at then?

  • I'm happy to hear that!

    These are our recommendations for cannabis, but they apply to most popular plants we grow indoors.
    We recommend 150 PPFD until the second set of leaves are showing. Progress towards 200 PPFD when the second set of leaves have unfolded. When your plant is 4"/10cm tall and/or has three sets of leaves, it should handle 250 PPFD quite well. When it is has become a young adult and is in its vegetative phase, slowly work your way to 400 PPFD, or slightly higher. When switching to flowering, an intensity of 600+ is recommended. When light intensity passes 500-600, photosynthesis will slowly become light-saturated and instead become limited by the availability of CO2. I recommend to not grow in intensities higher than 900-1000 PPFD, as this is where photosynthesis in cannabis starts to become more or less saturated, but it could be done in the late stage of flowering if you are on point with watering, temperature, nutrients, air humidity, etc.
    If you grow tomatoes and peppers we recommend stopping somewhere around 600 PPFD for the benefit of a larger light footprint.
    If you grow kitchen herbs such as basil, dillweed, parsley, etc, we recommend stopping at 400 PPFD.
    If you grow salad and leafy greens we recommend stopping at 300 PPFD.

    150 PPFD is achieved at 36/90cm
    250 PPFD is achieved at 30
    400 PPFD is achieved at 22/55cm
    600 PPFD is achieved at 18
    900 PPFD is achieved at 12"/30cm

    The blue button emits 38% of all light when both buttons are used. In other words, we have to do some math to figure out the new height you should have your lamp hanging at, if only using the blue button. Looking at our intensity maps, we can multiply any value with 0.38 to see the intensity produced by the blue button alone.
    If you want to give your plants 150 PPFD during seedling-stage with both buttons, hang the lamp at 36/90cm.
    If you want to give your plants 150 PPFD during seedling-stage with only blue button, hang the lamp at 22
    /55cm. (400*0.38 = 152)

    Never hesitate to reach out again in the future if any other questions arise :-)

Quick reply