It’s important to avoid giving too much N while plants are budding, as too much Nitrogen prevents proper bud formation and results in lower yields and airy buds. Your plant is showing a nitrogen toxicity. Many new growers accidentally give their plants give too much Nitrogen, especially in the flowering stage. This results in dark, shiny, clawing leaves. But cannabis plants need relatively low levels of Nitrogen in the second half of the flowering/budding stage. While your plants still need N (nitrogen) during flowering, too much N at this stage will prevent your plants from forming buds properly, resulting in lower yields, less potency and possibly inferior buds.
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