by Bridget Tisthammer
We are thankful for all your kind words of concern and encouragement during our recent flooding event. The waters have receded and we’re busy cleaning up. As you can see, we’re almost back to normal. The flood was devastating, but there’s nothing on the property that we can’t fix!
In the meantime, you may be dealing with some flood damage in your own garden. If you have a vegetable garden that was covered by flood waters, here are some tips to help you sort through the damage.
Throw away any vegetables that are eaten raw, such as leafy greens like lettuce, cabbage and spinach; and soft fruits, including strawberries, raspberries and blackberries. Some leafy crops, such as chard, beet tops and spinach, must be cooked thoroughly before eating. Use the sanitizing procedure described on this page before cooking.
You can also save root crops like carrots, potatoes, beets and radishes by washing them using the sanitizing procedure.
Throw away any soft-skinned vegetables, such as tomatoes, peppers, peas, beans eggplant and summer squash, which were in contact with flood water. You can wash and sanitize hard-skinned crops such as watermelon, pumpkin and winter squash using the procedure described here.
Unfortunately, no one can tell us for sure what contaminants were in the flood water—it could contain chemicals, oil, sewage, bacteria or parasites. For this reason, do not try to grow anything in your flooded garden for 90 days.
Was your turf damaged by the flood? Tony Koski, turf specialist with the CSU Extension Service, provided the following information:
As soon as flood waters have receded, clean up any debris that the waters deposited on your lawn. This includes rocks, glass, metal, wood and piles of leaves. If you have a layer of muck—that thick, black gummy soil that the waters carried down from fire-affected areas—you can try to remove it by shoveling and washing with a garden hose and jet sprayer. Depending on how much muck you have, this may not be possible.
It may take two to three weeks for your turf to dry out, depending on the weather, your soil and how quickly the area drains. At this point, you can measure the amount of muck on your lawn to determine the next step.
If you have less than one to two inches of muck, and your lawn was covered by water less than four days, it has a good chance of recovery. Check for new shoots of grass to determine if your lawn can recover. Once regrowth begins, it will slowly continue until the lawn has completely filled in. Be sure to aerate your lawn this fall. When you see some regrowth beginning, go over the lawn three to four times with a core-type aerifier. This will help break up soil layering problems and improve soil oxygen levels. Then fertilize the lawn, following the label instructions, in October.
You can also overseed after aerification if you see any thin areas in the lawn or if parts of the lawn aren’t showing new growth. Use a seeding rate of five to six pounds of seed per 1,000 square feet. Rake the lawn lightly to move the seed into aeration holes. Water the lawn to keep it moist, but not soggy.
If you have two inches or more of muck, the chances of the lawn recovering are slim. You may have to resign yourself to the fact that your lawn (or at least part of it) will need to be reestablished. One option is to remove as much of the muck as you can down to the level of the lawn. This may not be practical due to the size of your lawn or the amount of muck to be removed. An easier option may be to rototill the muck and damaged grass into your soil as deeply and thoroughly as possible. Avoid allowing the soil to remain layered—to have a layer of muck, a layer of dead grass and a layer of soil. By thoroughly mixing the three layers into one homogenous layer, you are creating a new root zone for the new lawn. After you have leveled and firmed the new soil mixture, you can seed or sod the lawn.
As always, we are here to help you in your quest to be a successful gardener so please feel free to contact us regarding questions related to the flood or any other gardening questions you may have.
Originally published on September 30th, 2013. Updated on December 5th, 2014.