Acapulco Gold photo/fem growing in soil. I’m using Jack’s Nutrients Part A, Part B, and Epsom salts. This is the first time I have used Jack’s.
It has been in flower stage for about two to three weeks. Based on this chart that I downloaded and compared to the leaf I cut this morning, am I correct in that it looks like there is a Potassium deficiency?
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Hey Art here is what Grok said about yellowing leaves and purple stems. Smoke a fat one before reading hope it helps.
Yellowing leaves and purple stems in cannabis plants typically indicate nutrient deficiencies, environmental stress, or genetic factors. Here’s a breakdown of the potential causes:Yellowing LeavesNutrient Deficiencies:Nitrogen Deficiency: Common cause of yellowing, especially in older, lower leaves. Leaves turn pale green, then yellow, and may drop as nitrogen is redirected to new growth.Magnesium Deficiency: Causes yellowing between leaf veins (interveinal chlorosis), often starting in older leaves. Epsom salts or magnesium supplements can help.Iron Deficiency: Affects younger leaves first, causing yellowing with green veins. Often linked to high soil pH locking out iron.Potassium Deficiency: Yellowing or browning at leaf edges, often with a scorched appearance.Watering Issues:Overwatering: Leads to yellow, droopy leaves due to root oxygen deprivation or root rot. Check for soggy soil and poor drainage.Underwatering: Causes wilting and yellowing as the plant becomes dehydrated.Environmental Stress:Light Burn: Too much light intensity or proximity to grow lights can bleach leaves, causing yellowing or white patches.Temperature Stress: High temperatures (>85°F/29°C) or cold (<50°F/10°C) can stress plants, leading to yellowing.pH Imbalance: Incorrect soil or water pH (ideal range: 6.0–7.0 for soil, 5.5–6.5 for hydro) prevents nutrient uptake, causing yellowing.Pests or Diseases:Spider mites, fungus gnats, or fungal infections like powdery mildew can damage leaves, leading to yellowing.Root rot from pathogens like Pythium can also cause yellowing due to impaired nutrient uptake.Purple StemsNutrient Deficiencies:Phosphorus Deficiency: Often causes purple or reddish stems, especially in cooler temperatures, as phosphorus uptake slows. Leaves may also darken or show purple hues.Magnesium Deficiency: Can contribute to purpling in stems alongside yellowing leaves.Temperature Stress:Cooler temperatures (<60°F/15°C), especially at night, can cause stems to turn purple as anthocyanin pigments (responsible for purple/red colors) accumulate. This is more pronounced in strains with genetic predisposition to purpling.Genetics:Some cannabis strains naturally produce purple stems or foliage due to high anthocyanin content, especially in cooler conditions. This is not always a problem unless accompanied by other symptoms like yellowing or stunted growth.Light Stress:Intense light or LED grow lights with specific spectrums can enhance anthocyanin production, leading to purple stems.Diagnosis and SolutionsCheck Nutrient Levels: Test soil or nutrient solution for pH and nutrient content. Adjust with appropriate fertilizers (e.g., nitrogen-rich for yellowing, phosphorus-rich for purple stems).Monitor Watering: Ensure proper drainage and water only when the top inch of soil is dry.Adjust Environment: Maintain temperatures between 70–85°F (21–29°C) and humidity at 40–60%. Keep grow lights at recommended distances.Inspect for Pests/Diseases: Use a magnifying glass to check for pests or fungal signs. Treat with neem oil, insecticidal soap, or fungicides if needed.Genetic Consideration: If the strain is known for purple traits and no other symptoms (e.g., stunted growth) are present, purpling may be normal.If symptoms persist, provide specific details about your setup (soil/hydro, lighting, nutrients, etc.), and I can help narrow it down further. Want me to search for recent posts or studies on this topic?
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Looks like that to me also Hap
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Thanks. Since I am not familiar with using Jack’s A, B, and Epsom salts, what do I do to fix this? The other two plants (identical to the Acapulco) appear fine, although not quite as far along in flower stage.
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I’ve never used Jacks so I don’t know what to tell you about that. But that plant is hungry which means it needs more food than the others. So increase your nutrients a little bit in other words make it a little bit stronger for that plant… baby steps, not too much.
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Many thanks! Even though this particular plant is just 3 weeks into flower, I hope I haven’t ruined or stunted its growth.
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Exactly what I’m going to do. Thanks!
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Nope. Not ruined. Just working up those big ol buds shes about to have. Shes just letting you know she can take a stronger nute recipe.
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I third that notion
Marty
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