Rose soil - what to add to make a good mix

[bikerbo]

Hi there all !

I need to make a soil mix for my new grow. For the last time i used a ph 5,5-6,5 soil, with nothing added, and it wasnt worth keeping the plants after 2 weeks.

I want to grow autos, and these are known for pH sensitivity.

I bought Soil rose with pH of 6,0-6,8. And it is 14-16-18 NPK ratio.

Should I add dolomite lime ? The pH seems correct, but maybe it will work as a pH buffer ? What do you think ?

What else should I add ? Some perlite ?

Please help and cheers, B

 

[bikerbo]

ok so this is my idea :

20 liters of rose soil (ph 6,0-6,8)
5 liters of coco (ph 6,5)
5 liters of perlite
mycorrhizae
some dolomite (or not)

what do you think, would it be good to start seedlings ? and enough nutes for 2 weeks ?

 

[s00thsayer]

You didn't list the ingredients of your "rose soil" mix, only the pH and the NPK of the time released fertilizer so it makes it hard for people to give you advice. I don't like soils that have time released fertilizer mixed in. A peat moss, perlite, dolomite mix works well for me, like promix or sunshine 4.

 

[bikerbo]

This soil has some added nutes in it : called PGMIX hydro

it contains 14-16-18 NPK (NO3 and NH4 nitrogen forms)
also : B (0,03%) Cu (0,12%) Fe (0,1%) Mn (0,16%) Mo (0,2%) and Zn (0,04%)

The "rose soil" is made from : sphagnum peat moss (light and dark) , some PGMIX added, and some chalk to raise the pH (thats what the bag says)
also it says : organic matter : 85%, air capacity 25%


I'm going to use 20 liters of this soil mix, 5 liters perlite, and 5 percent coco to make a bit lighter for the seedlings. Also i'm going to add Mycorhizzae - mix it in the soil when planting seeds. Should i also add dolomite lime ?

 

[s00thsayer]

Yes, your plants will need the magnesium in dolomite so add it. You can skip the coco. Because your soil has fertilizer in it you won't want to feed your plants with anything but water until it shows signs of needing more nutrients which will be a month or more...it should say on the bag.

 

[bikerbo]

OK i'll ad some dolomite. is a cup per cubic foot good or half cup per cubic foot ? i dont want to raise the pH too much

i also have mycorrhizae, should i mix in evenly with the soil and perlite, or wait till seedlings sprout and then use it ? it's in a form of small granules / balls