How to adjust alkaline soil for outdoor marijuana growing?

I want to grow marijuana outdoors but where I live, the soil is extremely alkaline. What do I do to adjust it?

You can adjust alkaline soils with naturally acidic sulfur. You can also neutralize them using acidic organic materials like coffee grounds, manure, cottonseed meal, pine needles, and citrus rind. Measure the pH level and then ask someone at a nursery for a recommendation to adjust it.


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Take a soil sample to your horticulture extension service and have it tested. They can give you a treatment plan to bring the pH up to an acceptable range. I still recommend growing in planter boxes where you can control the soil content more.

Again I do not grow outdoors, but I feel having the best control of the soil is key, Everyone I know that grows outside uses elevated boxes with supersoils they mix.


i grow only outside. having a very secure south facing garden. last season i planted in 70 liter containers. the one and most important mistake i made was not having the right ph value from the beginning. i fought all summer to bring ph down
to around 6.5. i used 20% vinegar. it was hard going. ph just wanted to go up.for watering i used regular tap water and vinegar mix bringing the ph up to around 6.0. that’s all i could do. was afraid that it will be low yield and quality. at the end it turned out acceptable on both counts. for this coming season i want to make sure that the soil will be the right ph value.
where i live and in my garden the soil ph is around 7.5 so planting in the soil would be futile.
need some input on how to plan and prep the soil.