C02 Generator for Giant Pumpkin Plants

Now that my plants are in the hoop house I've added some CO2 generators to the hoop houses.  This is the 3rd year that I've done this.  You just need some yeast, sugar, warm water, old pop container and a straw to get it going.  I first drill a hole slightly smaller than a straw in the lid and then put a straw into the hole and glue the straw to the cap to fill any holes around the straw.  I then put warm water, 1/2 cup of sugar and a packet of yeast into the pop container and put the lid on the top with straw pointing out towards the pumpkin plant, but just short of the plant.  This video I found on youtube has a similar design to the one that I describe.  I use a larger pop container and I only fill it 1/3 of the way full of water.  The CO2 will fall from the straw down to the pumpkin leaves.

When the hoop house is closed up at night I think there is enough of a seal to allow at least some of the CO2 to build up at night.  One study found that with a proper addition of CO2 plants can grow up to 50% more.  I've never seen anything like that with my plants in the past, but I figure a little extra CO2 can't hurt.