Hey...I copied and pasted this from an outdoor auto growing guide I am in the middle of writing...hopefully its of some use, there is still a lot I want to add to this section before the guide will be released
Determine what style of grow you want to go. Do you want to use pots? If so, pot size needed will be determined by the strain you want to grow. If you choose a giant auto strain like the autoultimate and only use a 2 gallon/8liter pot it will only get so big. But on the flipside, several smaller quicker auto strains would do fine in a limited sized 2 gallon/8liter pot. Myself I prefer to grow big auto strains outside. I only have a tiny indoor room to flower auto plants, so i pick big girls for the great outdoors. For this reason i do not use pots at all...ive been growing photoperiod plants for many years in the native soil and they grow very big, so i assumed that it would also work well for autos, and i wanted to add autos to the outer perimeter of the photoperiod plants, so when get huge, the autos will be harvested. The only thing i added to my nicely balanced soil (PH 6.5) is 1/2 cup of lime, and 4 liters/1 gallon of well rotted horse manure per plant for some nice additional micronutrients.
Root bases that can travel freely will become immense, and have an excellent nutrient uptake, giving the ability to fuel lots of flower. Growing directly in the ground has advantages. Going on vacation? Give the plants a good heavy drink before you go and they will be fine in a week when you get home. That will not likely happen in pots. Of course the disadvantage is that once in the ground, they are there for life. A potted plant can be moved to an outbuilding to shelter from rain or nightly dew, or even in the house at night if the humidity is high, and you run air conditioning, chances are its much less humid in the house. Its all a gamble if you live in mold country, so you have to make the call whether or not in the ground or in pots is the best choice for you.
