Dude just do yourself a favor n forget MG products all together....plus the pee idea isn't great either IMHO. Get yourself a full nute kit (I use technafloras full kit comes with mixing chart n everything your plants need. Next buy a basic soil mix ( I use 50/40 peatmoss / perlite n 10% vermiculite) next find strains that grow good in your climate n such (lots of research).
Soak your beans in a cup of water somewhere dark n above 50def F. N let them soak for 12 hours. After 12 hours go back poke the seeds with your finger till they sink (if it sinks it's a good seed floaters are bad.). Let soak for another 12 n then plant seeds into your soil mix in 16oz solo cups with lots of drain holes poked in the bottoms. Bout 1/4 inch down. Wait 3-7 days (don't need light at this point). Wait for them too come threw n then on colder rainy days just leaves them on at a window. N on nice days right in the sun ( mine go in all day sub right out of the gate) after they have about 2 -3 weeks start feeding 1/4th strength nutes (go by the chart it comes with). For about a week n then go half strength n then full week after week Now, after they have a full set of 3finger leaves or 2 transplant too 2 gal pots in the same soil mix. Now don't over stress over rain and kinda cold warther at this point they will hold up. And try and bury the stem up too your first set of 1 finger leaves too sturdy them from hard wind n heavey rain. Plus it will grow roots out of what got buried. Then after they get about a foot or foot n a half tall transplant into ground or bigger pots n follow the feeding chart as usual. And your done! At the end of the year u should have something that looks like this
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