Hello, I started some Gorilla Glue autos, four under 1500watt LED and four under 1000watt LED. The four under the 1500 are growing well but are very short and bushy (after 3 weeks) and the four under the 1000 are growing tall and slender. Should I start all of my plants under less light? Move the light higher for seedlings and sprouts? All eight do look healthy. Thanks.
Hard to give you a definitive answer without knowing exactly what light models you have. Stated wattage is misleading as manufacturers state “Equivalent” wattage and often exaggerate the claim.
But one thing is always the same, if the seedling is stretching the light is too far away, and if it is too squat you are too close. You want a little separation between the nodes for secondary plant development and light penetration to leaves.
If you know the brand and models of your lights you can get some good advice from the growers here.