R.J.
As far as the tomatoes... upping the heat, tweaking the water, and messing with the light cycles will do it.
Light... well that's really a pain... and I would suggest you DON'T do it. (As a matter of fact; never plant near a street with sodium lights. -The orangy colored ones. Those lights feed plants and keep them in a vegetative cycle, instead of a fruiting cycle. They'll still fruit... probably... just not very robustly. Because the plant gets confused. Ideally... start indoors with a 24hour constant light cycle for some wicked vegetative growth, then move outdoors for day/night cycle (or start turning off the lights indoors). You CAN start messing with fruiting cycle light patterns to convince the plant it's about ot be winter so they'd better speed the frack up... but if you do it wrong it halts the fruiting cycle entirely as the plant goes dormant. Hence not the best area to start messing with.
Heat, however = Painters plastic. Just cover them up during the daytime, to refract some sunlight times a bunch, and then yank it at night. (You want them cold at night. Not aircon cold, just a significant difference. Tomatoes really love being yanked around with extremes). BUT BUT BUT
You want to dry them out.
Tomatoes do best when you let them get almost wilty dry (or heck, even wilty dry) and then SOAK them. To really soak tomatoes you need to water twice. Water once like normal (quite saturated), and then water again 15 minutes later for twice as long. I'm talking some serious saturation. Then let them dry out again. Then saturate. Dry. Saturate. Silly tomatoes.
In order to do this (hence the 'but but but')... they need to evaporate. So when you throw plastic over them... do NOT tent them. You want the soil to get hard dry, and it won't if they're steaming and dripping.
ALSO... and this is a little too late for this crop... if you have boys... have them pee on your tomato plants whenever possible. Tomatoes are greedy plants, and use up a LOT of the nutrients in the soil. The ones they need the most are found in worm castings and human pee. Adding worm castings to their water supply during the vegetative cycle... and then peeing on them will grow you some bonzer tomatoes that fruit heavy and fast.
((If you don't have boys, you can save your own pee indoors and then mix with water and pour on their roots. Don't 'save' your pee, though, because you want to be adding nitrogen and uric acids... not ammonia. While one CAN add synthetic concentrated nitrogen... that can burn your plants or make them 'addicted' to high levels which creates sickly plants with low flavor -but pretty color... hence why miracle gro is popular amongst people who don't know better. Yep. It's gross. But plants eat gross things. Like dead animals (add blood meal and bone meal to your soils), decaying plants (a good compost), poop (worm castings and manuer... worm poop and cow poop), and pee. Pee turns to ammonia so quickly that you won't find a 'pretty' sounding name for it... but it something these kinds of plants need to reach their best potential.))
