Newbie, indoor, nutrient question

I have an auto fem blueberry that has just entered the flowering stage (32 days old). I have it planted in a roughly 70/30-60/40 perilite to soil mix. Bothe the soil and perilite have added nutrients.

N - .8%
P - .1%
K - .1%

NPK - .07%

Should I add extra nutrients? The plant is not getting nutrient burn, at this point. I would like to make sure it is getting optimal feeding, but I am unsure if I should add them or not. I have been testing the soil for pH, N, P, K. The tests say that N is pretty high, P is pretty high, but K is adequate… I bought some Flower Power.

Please feel free to give me your thoughts.

Any chance you’ve measured runoff TDS? Might be a good indicator of what is still left in the soil for nutrients.

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I have a 5 gallon pot, which I think is way to big. I could wait until the next watering and do that test. Do you have a suggestion for a tester?

I use this one. I’m thinking, for example, if you’re putting 100 TDS water in and 200 TDS out, the plants haven’t used all the nutrients yet. Not knowing, if I were a betting man, I think you’re probably ready to start nutrients at 25% or 50% of recommended and see how they like it. Then, slowly increase.


And I use 5-gal pots. I think you’re okay with that.


I feel like the 5 gallons are too big, but I did plant my plant a little low. I thought 3 gallon might be better.

What is 100 TDS water? Sorry man, I am a total newb. The last time I grew was 20 years ago and we did was add some chicken manure to water and use that.

Does the meter just read out TDS and that way I will know?

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Okay, sorry. The numbers were just examples.

The meter measures Total Dissolved Solids in water. It’s the stuff in your water like salts, metals, lead sometimes, etc.

If you measure your water going in, you can then compare it to what comes out the bottom of the pot. If the runoff is higher than what you’re putting in, nutrients are “collecting” in the soil, meaning not being consumed by the plant. It’s an indicator you’re overfeeding.

So, my thought was that you can measure your water then measure your runoff to compare. If the run-off is a fair amount higher, you might want to wait on feeding. If they’re the same or less, you can probably feed.

I hope that makes a little more sense.

I think 5-gal pots are the appropriate size. Root balls can grow huge and you want to give them as much space as you can, within reason.


Also, the soil you used isn’t super “hot”. The NPK numbers aren’t super high like some soils I’ve seen. That said, always better to get soil and perlite that does not have fertilizer already in it.

At 32 days, I’m guessing you can start feeding, starting at 25% or 50% of the recommended amount.

Are you checking PH? If not, you definitely want to order a PH meter. More important than TDS, if you had to choose one, IMO.


Thanks so much. I bought a meter and will check the in and out. I will then try to feed the plant accordingly

No problem. Make sure to check PH as well :slight_smile: Good luck!!!

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will do, I have been good about the pH, it is around 6.5-6.8

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moved topic to the appropriate section

what seeds are worth buying…