greenhouse seed co powdered nutes, no idea

[lipnobody]

heres the lowdown guys hoping youse can help a fella out.

first timer
indoor grow 1x1x2 400W HPS auto northern lights, soil substrate in 3.3gal rhizo smartpots

ive gone and bought the greenhouse powder nutes becasue i was unsure with faffing about with liquid nutes and overloading my girls!
i have the biogrow and biobloom packets and ive tried my hardest to figure out via greenhousefeeding website how to use them but still pulling my hair out here,

the soil is already pre fert enough for 3weeks ive been told, now on their webpage it says i must mix in 3gms per lt of substrate but if the substrate is already pre fert to use half the doseage! and the biobloom also states this too.

nowhere can i find any info regarding if i should mix in both the biogrow and biobloom together before i germ my auto seeds in the pots! or if i should add the biobloom as a top dressing once the first flowers are starting

im petrified of killin the seedlings 🌱 with so much nutrients

any help or knowledge about these would be much appreciated dudes and dudettes
ive been told i shoulda went with liquid nutes but hey ho ive got these and cant return them and dont really want to go out and buy other stuff due to saving the pennies


and thanks for the add, looking forward to learnin loads from you friendly bunch

[D.A.A.S.69]

Most good store bought soil has enough nutrients in it for seedlings for at least a month, I wouldn't add anything until the seedlings look like they need some, plus autos don't really need much nutrients. Good Luck Lipnobody.

[lipnobody]

i know the soil i have is good for 3 weeks.
my question is reqarding the powdered nutes and how to use them.

[lipnobody]

pots arriving tomorrow was hopping to get crackin, hhheellppp

[Weed Pharma]

I use both liquid and dry throughout most grows- specifically mostly liquid during veg in coco/perlite , then mostly dry during flower in Roots Organic Original.

I grow auto's in 3 gallon containers and sprinkle 1gram of dry per plant when topdressing, which is what I recommend after reading the greenhouse feeding website.

Auto's require very little in the way of nutrients, so what I would suggest (and what I use) is 1gram of grow at week #2 & #4.
Once in flower use 1gram of bloom at weeks # 1 & #3.

You can always add more if you see a need.

[lipnobody]

thanks dude, just gonna go for it starting with 1/6th of the recommended dose then build it up if needed.
yeah autos for my first time cant really do any wrong i guess.

off the deep end