Top dressing autoflower in seedling stage

My auto seedlings are around 9 days old. 3 gallon pots. Soil is 1/3 fox farm happy frog, 1/3 for ocean forrest and 1/3 perlite. I filled pots just over 1/2 way to allow for topping off with maybe a mix of ffhf and ffof mix near seedling and ffof to cover the rest of pot. My gals look good, but are maybe close to 3inches. A bit long. Will I burn the seedling if I add more soil at this point? That apprehension to burn the roots from too hot mix is what is preventing me. Love feedback. Should I wait and let her be leggy, so to say? Using spider farm 4000 at around 26 inches and 60%, no dimmer.

Your soil has plenty of nutes in it. There is no need to top dress such a young plant.

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Agree there are enough nutes. I just don’t like how leggy she is. They do look nice otherwise. Thanks for reply!

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Inadequate lighting is the most common cause of leggy seedlings. Lower your light a bit.

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You can back fill your pot without additional problems as long as you’re using the same (or similar) mix. I do it all the time.

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Yup Id top her up with Happy Frog without a worry. More soil helps support the stem, but addressing the issue would be my first course of action.

Stretchy seedlings are normally not intense enough lighting. What u running at what distance?

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I have 8 gals in 3 gallon cloth pots. They are on one side of a 5x3x6 (or so) tent under a spider farmer 4000 light. 26 inches, around 60%, not using dimmer. Lots of humidity and nice air circulation. I increases lights slowly over their first week. This is day 9. These lights are strong! Will take a few pics. Thanks for your imput


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The girls are having their 6 hours rest, so I used a flashlight to illustrate how much room is left in the pot. The stem is 3inches. Top dress two inches with ff happy frog for now because less nutes and top dress in some weeks once in veg with ocean forrest? How does that sound? It’s my 3rd grow, 1st with autos.

Sounds about right to me.

When you say top dress most people are thinking you mean adding dry nutrients to water into and feed your plants. I think Purp is correct in assuming you’re talking about topping off the open space in your pot? If that’s correct I agree with him, more soil and happy frog is gentle which you want for a baby.

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Ah, good clarification! I appreciate that. Yes, I mean to add more soil. I will do an inch or two. I want a few inches left in the pot for ocean forrest once the babies are teenagers; sometime in veg when they have bushed out a bit! I have pleanty of room in the pots yet! You guys are so kind to help out!

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Awesome.

I’ll say this… normally you would only add to the top of the pot if your seedling stretches and needs more trunk support. Typically if you wanted to add more heavily amended soils so a plant can “grow into it” you’d fill the bottom couple inches and the outer ring in Ocean Forest after starting your seedlings in something like happy frog, That way as your plant grows and the roots stretch farther the reach more heavily fed soil. Hope that helps for the future

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I’m going to ponder what you said…and get back to you. I have to visualize everything.

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Imagine it this way. You have your seedling in a solo cup of happy frog growing like a beauty. You intend to transplant into a 5 gallon of ocean forest.

If you filled the 5 gallon pot with ocean forest but left a hole that fits a 1 gallon pot… And filled that with 50/50 happy frog and ocean forest…

As your roots continue to grow outward with the plant growth your plant would be reaching more and more nutrient rich soil as it continues to expand its root base

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Yes. It just made so much sense! It was a “eureka!” moment. Great foe next time. As autos I decided to just sprout the seed and plant it direct in the final pot so as to not stress her in the shortened life of a rudellia.

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It is day 19 under lights. I noticed just the tiny tips of new growth on this gal and would like to address things for her. I don’t believe it is a mag/ cal problem…what can the yellowing of just the tips of new growth represent? Lights too bright?they are at 80% sp4000 about 23 inches from top of plant. Can it be a slight nute burn? My desire is to do organic and as much just from living soil which is combo of ffhf and ffof and perlite. I left room in the pot to add more ffof soil as time goes. I also have molassas ( not used yet), and these two products, the mykos I sprinkled over the spouted seed and have not used since and the pridesland is for flowering…not there yet. I’m in veg and they are growing nicely daily. Please advise me concerning those yellowing tips that are beginning to present.

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10 Most Common Reasons for Yellow Leaves

  1. Root pH
  2. Poor Watering Practices
  3. Nitrogen Deficiency
  4. Light Burn
  5. Heat Stress / Cold Shock
  6. Magnesium Deficiency
  7. Iron Deficiency
  8. Not Enough Light (Seedlings)
  9. Bugs or Pests
  10. Bud Rot

When Not to Worry (Pictures of Normal Yellow Leaves)

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Some growers push the nutrients to produce the product they want. They are looking for “burnt” tips as an indicator.

I don’t do that. I’m just the opposite. I use Happy Frog dry amendments and feed my plants at half strength.

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Im one of those guys lol. Nothing to over worry about. Just a bit of burnt tips

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