Is it safe to eat lettuce after heavy rain?

If it has recently rained heavily, do not harvest your lettuce until 24 hours after the rain stops. This gives the plant time to metabolize some of those nitrates, and it allows the leaves to dry out; mildew, E. coli, etc., will flourish on wet leaves. I learned this the hard way when my stomach took a battering from E. coli after picking lettuce that was still wet from the rain.

Find out why the nitrates increase after rain. Nitrogen from the soil is absorbed into the leaves through the roots when the soil is wet. By waiting twenty-four hours, you allow the plant to naturally consume the nitrates, as it normally would. If you have them, test the plants with nitrate strips. You will find the level has dropped by around 40% in a day. You don't want it entering the food chain!

Check the underside of leaves for bacterial contamination, and throw away any leaves that have soil splashed on them. Wear gloves when harvesting, and use 70% alcohol to sanitize your tools. Keep contaminated produce away from other produce. By following the above steps, your risk of E. coli infection will decrease dramatically.

Improve your garden drainage before storms roll in. I top dress my raised beds to about 30 cm (roughly 12 inches) in height; as the soil is richer with organic matter, the bed drains better. I use steeper mounds, sloping the planting areas away from the paths. Consider French drains in wet zones. Most of the time, my raised beds drain down within 2 hours after heavy downpours.

Commercial growers implement Food Safety Plans. Use proper protective measures during heavy rainfall. Test all irrigation water every month and keep records of the harvested products. Most importantly, all of these practices satisfy the GAAP Certification requirements. However, Home Gardeners can also apply these principles.

Read the full article: When to Harvest Lettuce for Best Results