We have seen a lot of rain in the past couple of weeks. And, in many locations, we have seen a great deal of flooding. Long-term flooding can cause a great deal of damage to our landscapes and gardens, but thankfully we saw short-term flooding that many of our plants will be able to survive.
Lawns are very resilient in flooded areas. Many of our lawns are still quite wet from flooded conditions. It is best to stay off of wet lawns to avoid compacting the soil. Wait until it has dried out before mowing, driving equipment over, walking excessively over, and cleaning up the debris that may be on the lawn. Turfgrass can survive 4-6 days submerged, according to Missouri Extension. Most of our floods receded prior to 4 days, so the lawn should survive. We may see an increase in lawn diseases this summer due to the high amounts of rain and floodwater that affected them this spring.
Floods also could have damaged trees. Many trees that are planted near rivers and streams can withstand longer periods of flooding. However, when the floods move into our towns, it can cause problems to our other tree species. According to the University of Wisconsin Extension, most plants can tolerate a few days of flooding during the growing season. Certain tree and shrub species are going to be less tolerant of floods, but for the short time our floods lasted, our plants should be fine.
Once the flooding recedes, make sure the roots don’t have more or less soil on them than before the floods. If more than 3 inches of soil or debris was added to the ground surrounding the tree, remove the excess to allow the plant roots to breathe. If water pushed soil off of tree roots, add soil back to those areas to ensure they are not more exposed than they were before the flooding.
Vegetable Gardens would be more of a concern for food safety reasons. The short period of time that they were underwater, should not affect their growth. Floodwaters are typically not very clean and they can carry bacteria and other debris with them as they move across the land. It is best not to eat any vegetable raw that was at any time under floodwaters. So the best recommendation for lettuce and spinach would be to discard the entire plant. Vegetables that were submerged by floodwater should be cooked to make them safe for consumption. The vegetables that may have been planted but are still too young to produce yet would be safe for consumption when they mature. The University of Wisconsin also suggests to increase safety of the vegetables that haven’t been under floodwater, cook them, or at least wash them well and peel them, if possible, before eating. Be careful to not allow any vegetables to fall onto the ground where they can come into contact with bacteria that could still be on the soil. A layer of mulch will help reduce this issue.
Our plants should all survive fine from the few days of flooding that many of us saw. The only way to know for sure what damage occurred to our plants is to wait and see. These plants were put under a great deal of stress and therefore may be vulnerable to many disease and insect problems through this summer. Take extra care of them and watch for signs of problems to treat them early in the infestation.