the bigger the hole u dig the bigger the roots can grow and the bigger the plant you will have. i suggest starting them in small pots and babying them if u can and transplanting them to your site once they have grown to atleast 8 inches or so. this will give them a much better chance of survival.

dig 1 hole per plant with atleast 3 feet between them. once your plant gets bigger than a foot or so a spray bottle isnt gonna cut it. u need to saturate the soil so the roots can grow. when it is dry water again (might be 2 days might be 2 weeks depending on your weather) .

i would bring in some organic soil and some promix to ammend your holes. id dig your holes atleast 2ft. x 2ft. prefferably bigger. if the soil really sux replace it with what you brought in or mix alot of it with it. scatter the dirt u remove so it doesnt draw attention to your site.