It’s really hard to find a sativa that will finish that early and still be good quality (serious 6 is your best bet). You’re looking at mid-Oct to end of Oct for most sativa. If that is your route though the chances you find it, get it shipped, germinated, hardened off, and planted by July 4th is very slim and the quantity won’t be the greatest. Since this is your first outdoor grow, you’re better off starting a few of the strains you have on hand as soon as possible (like today). Yourll most likely come out with a good sized crop and even though they may not be best suited for the environment you should use this as a learning experience to learn all the variables New England growing throws at you. Then go into next season well prepared and killed that grow. Growing outside is playing the long game (most of the peeps on here have been growing outdoors 10+ years), be patient and your grow will pay you back huge with more weed then yourll be able to handle (outdoor harvesting is a lot more laborious than indoor). Best of luck!