Walking on or working with wet grass can damage it. Wait until you can walk on it without leaving wet footprints; or the soil should form a ball in the hand, then crumble when pressed. If the squeezed ball of soil drips water, it’s still too wet. Do not attempt to mow a wet or saturated lawn as you risk compaction and ruts. If you want to mow the lawn once it has dried out, set the mower blades to the highest possible cutting height.
If the lawn has been flooded – not just from rainwater but actual floodwaters – silt left behind may be contaminated, so wear rubber boots and disposable rubber gloves.
If a lawn is covered with under an inch of silt from flooding, it may recover. You should attempt to remove silt, along with any debris, either by hosing or raking it off. Unfortunately, if your lawn has been submerged for over a week or if it is covered with more than an inch of silt, it may need to be re-sodded, but this is best done in early Spring next year.
If you have less than three inches of silt, rent an aerator and use it on the damaged area up two to six times during the season, then top with sand or compost which will work into the holes. If the silt is over 3 inches deep, consider having it professionally removed.
Do a soil test to see what nutrients may have washed away or need replacing. Kits are usually available from the local agricultural extension service office, complete with sampling instructions. Results will tell you what major nutrients and the amounts needed.
Trees and shrubs
Scoop or rake silt from the base of plants and tree. Water and air need to reach tree roots, and since many of their feeder roots are near the surface, you’ll need to break up or remove silt as described for lawns. Even 6 inches deep around trunks or 3 inches deep over roots can be enough to smother them, resulting in a slow plant decline and perhaps eventually death.
Flowers and vegetables
As much silt as possible should be removed from vegetable gardens. In the case of flood waters, a general rule is that you should not harvest produce within 4 months of flooding as it may be contaminated. This does not apply to plants submerged from standing water such as rain water.
For annual flowers, remove as much silt as possible. For perennial flowers, many are tough and can emerge through a few inches of soil. For deeply covered perennial beds, it may be easiest to dig them up, then till the whole bed and start over.
Prepare for next time – improve drainage
Most minor drainage issues (standing water after a heavy rainfall for less than a day) are caused by clay soil, and most can be corrected by adding sand and compost and tilling the yard. This will require replanting the grass, but can help fix wet areas long-term.
A more serious drainage issue means that you have standing water after light to moderate rainfall or if the standing water stays for more than a day. One solution is a French drain, which is essentially a ditch that is filled with gravel and then covered over. You can also create a berm to redirect the water flow – great for specific beds that are getting flooded. Be aware that water will run somewhere else, which could create other drainage issues.
Creating a pond or a rain garden has started to become popular as solutions for yard drainage problems. Both solutions not only help collect excess rainwater, but also add a lovely feature to your landscape.
Rain barrels are another thing that can be added to help with drainage. Rain barrels can be attached to downspouts and will collect rainwater that would normally run into the yard, so that the yard doesn’t have to handle this extra water. Collected rainwater can then be used later when rainfall is low to water your yard.