How to prevent cross pollination in tomato plants

Tomato plants are actually self pollinated, so it may seem somewhat strange to even suggest you should try this however cross pollination in rare circumstances can occur. 

Tomato plants have perfect flowers which contain both male and female parts. So they are not normally insect or wind pollinated, however if an insect were to gain access to certain parts of a flower then pollen could be transferred to neighboring plants therefore crossing two different varieties. Since many growers of heirloom plants are wanting to save seed it is best to follow guidelines for preserving the genetic integrity of each separate variety. Blossom bagging is not essential, plants can be safely distanced with buffer zones added in order to grow different varieties without fear of crossing. We decided to blossom bag this year because we recently added bees to our small farm. Although bees tend to avoid flowers that are in the night shade family, and so far our bees have, they will in fact visit them if other food resources are not readily available . The below picture is from a Tommy Toe tomato plant with blossom bags.

The bag is simply a small cloth mesh material that contains drawstrings. The bags are 5 to 7" to ensure they are roomy enough for the clusters. We bag the flowers before they open, however not when they are too small. We simply apply the bag, pull the strings snugly, but do not over tighten them, and then we staple the bag to the string holding up the plants.Once all the flowers have been pollinated and we see little tomatoes we remove the bags and mark them with bright green flagging tape to ensure we know which ones are pure in case we miss some in the future. This can be done with other members of the nightshade family such as peppers and eggplant. These bags however are not advised for wind pollinated varieties such as corn due to the fact pollen could travel through the mesh. We employ a different system with corn. Is is important again to mention not to over tighten the bags since this could kill the cluster. Just snug enough so it won't fall during windy conditions. I hope this information is helpful in your gardening journey and if you need seeds, visit our store at 

www.southgaseedco.com

Thanks!