Why did my plants stop growing?? Seem small for age...

Just looking for some thoughts on why these plants are only as tall as they are for being a tad over 3 months old.
I have a bunch of these white widows but here are 2 that are a good average, didnt feel like shooting a crap load of photos. I have alot of plants, they all look like this.
They seem to look healthy, i feed them offten and water when needed.

Soil doesn't look great. Looks like it has been hot and dry. Also see what looks like mg deficiency.

What is the soil composition? pH?

What is the environment like? Temps/humidity? Rainfall?

what have you been feeding it?

How much water & how often?

I dug a 2x3ft hole
Soil for these plants were on a budget so I did garden soil with .07, .01,.03 with worm casting and perlite and regular dirt from garden.
ph is 5.7, temps have been high 90s, low 100s. I feed with bio bizz "bio grow". I water 1 gallon every other day.

that ph is low for soil, should be like 6.8

6.8??
All my reading and other people's input told me for outdoor go 5.7 to 6.5
anything above 6.5 is for hydro.

2012dmax said:

6.8??
All my reading and other people's input told me for outdoor go 5.7 to 6.5
anything above 6.5 is for hydro.

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I think you got your info mixed up between 6.2-6.8 is for soil 5.5-6.1 is for hydro

2012dmax said:

6.8??
All my reading and other people's input told me for outdoor go 5.7 to 6.5
anything above 6.5 is for hydro.

Click to expand...

Perhaps your reading comprehension is slightly off! Best hit the books again....

hmmm maybe I did get them backwards, even then would .4 ph make a huge difference?

2012dmax said:

hmmm maybe I did get them backwards, even then would .4 ph make a huge difference?

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Sure there are a variety of nutrients taken in at different ph ranges, if it is of by .2 it could lock out a nute... So yes when trying to give information, attention to detail is extremely important....