The best thing you can do is get the roots of the plant as healthy as possible before you go away. Start them off early as possible either indoors or outside in a coldframe. Pot up the plants properly check out oldtimers guide to roots. Prepare your sites by digging in plenty of compost and bone meal. Only water your plants if they really need it in the months before you go away. Give them a good drink and mulch around the stem before you go away in case of drought. If you want you can use water saving crystals aswell. But to be honest with the amount of rain weve had the last 3 years you wont need to water at all. I wouldnt get a grow partner in myself I work alone

Its handy having a good mate to dry it for me though
Hope this helps, youve made a great decision to grow your own, good luck.
O yeah dont bother with autoflowers go for sotmhing thats starts to flower early and doesnt take too long to finish, Durban poison, passion 1, easy sativa to name a few.
Wakenbaker