The short answer
Have the soil tested before you grow food in it, and read the result against EPA’s gardening guidance (page updated September 21, 2026). It has three bands. Approaching 200 parts per million (ppm), take precautions and grow deep-rooted crops such as tomatoes in raised beds. From 200 to 400 ppm, grow root vegetables and shallow-rooted crops such as lettuce only in raised beds of clean soil, and deep-rooted crops only in containers. Above 400 ppm, do not grow food in the existing soil at all.
Below 200 ppm is not a clean bill. EPA still asks gardeners at that level to wear gloves, to wash hands, produce and clothes, and to limit gardening when pregnant or nursing. It lists four ways gardening exposes people to lead: eating produce that absorbed it, eating soil left on produce, soil tracked indoors, and swallowing or breathing dust.
What EPA says to grow at each level
| Soil lead | What to grow, and where | Precautions |
|---|---|---|
| Approaching 200 ppm | Root vegetables and shallow-rooted plants in the existing soil; deep-rooted plants in raised beds | Gloves, and tools to limit soil contact; wash hands, produce and clothes after gardening; limit gardening if pregnant or nursing |
| 200 to 400 ppm | Root vegetables and shallow-rooted plants in raised beds of clean soil and compost or manure; deep-rooted plants not recommended, even in raised beds, unless grown in containers | All of the above, plus mulch or ground cover over bare soil, and peel root vegetables before eating or cooking them |
| Over 400 ppm | Shallow-rooted plants only, in raised beds with at least 16 in of clean soil on garden fabric, or in containers; root vegetables and deep-rooted plants only in containers | All of the above, plus cover bare soil or keep it damp, and add clean soil and compost or manure to the beds or containers every year |
EPA pictures a radish for root vegetables, lettuce for shallow-rooted plants and a tomato for deep-rooted plants, and names carrots, beets, turnips and radishes as root crops to peel. A result in mg/kg is the same number in ppm.
Get the soil tested
EPA lists three ways to have soil tested for lead: some local health departments test home soil, most state university and extension soil labs do, and soilSHOP events screen soil that people bring in. Ask for total lead; University of Maryland Extension’s lead page says to pay careful attention to the total lead values in the report.
Sample the vegetable garden and any children’s play area separately, and do not mix soil from several places into one sample. Maryland notes that lead collects in the top 8 inches, most of all in the top 1 to 2, and does not fade over time. The sources Maryland names put it beside old painted buildings, near busy roads (from old leaded fuel) and on old industrial and orchard land.
Until you have the result, EPA says to keep children and pets out of the garden. If you buy soil to fill a bed, ask the supplier for its test results, lead included, as the University of Maryland Extension suggests; buying soil in bulk lists the other questions to ask.
Why EPA’s figures and Maryland’s differ
University of Maryland Extension’s lead page (updated July 11, 2025) treats 50 to 400 ppm as one band. In it, Maryland lets every vegetable and fruit be grown in the ground, provided the soil is kept at pH 6.0 to 7.0, the top 8 inches is at least one third organic matter, phosphorus is added as a soil test recommends, and produce is washed and root crops peeled. Its reasoning is that plants take up little lead from such soil, and that the main danger is swallowing soil, much of it carried indoors on clothes, shoes and tools. It still describes 400 ppm as EPA’s most current figure for growing vegetables.
EPA’s gardening page now adds a step at 200 ppm. That is also the level EPA uses to screen home soil for lead at cleanup sites: 400 ppm until January 2024, when EPA lowered it to 200 ppm, a figure its October 2025 directive keeps. And EPA counts eating produce that absorbed lead among the ways gardeners are exposed, where Maryland rates that route low.
| Total soil lead | Maryland Extension |
|---|---|
| 10 to 50 ppm | Typical natural background; Maryland says no ill effects on health have been noted at these levels |
| 50 to 400 ppm | All vegetables and fruit in the ground, with soil pH 6.0 to 7.0, plenty of organic matter, washing and peeling |
| 401 to 1,000 ppm | Fruiting crops (tomato, pepper, squash, sweet corn) in the ground; leafy greens and root crops in containers or in raised beds of clean topsoil and compost at least 8 in deep |
| Over 5,000 ppm | Consider having the soil removed and replaced by a certified contractor |
Maryland’s page gives no planting band between 1,000 and 5,000 ppm.
Above 400 ppm the two part again. Maryland still lets fruiting crops grow in the ground up to 1,000 ppm and asks for 8 inches of clean soil under leafy greens and root crops. EPA, for anything over 400, keeps food out of the existing soil and asks for 16 inches of clean soil over fabric, for shallow-rooted plants only.
Where the two disagree, this site follows EPA: its page is the newer and the more cautious, and a bed built to its 16 inches also meets Maryland’s 8. Neither treats a low result as a reason to skip the precautions.
Building a raised bed over contaminated ground
Fill the bed with clean, bought soil and compost, and ask for the supplier’s test results. EPA puts the clean soil on a visible barrier such as garden fabric, so you can see where the clean soil ends. NC State Extension goes further over contaminated ground: seal off the bottom of the bed with an impermeable barrier so roots cannot reach the soil below, and drill drainage holes near the bottom. The bottom-of-the-bed guide compares the materials.
EPA’s 16 inches is clean soil, not wall height. Iowa State University Extension leaves 1 to 2 inches at the top of a bed for mulch, so a bed built for 16 inches of soil needs walls 17 to 18 inches tall, and logs, branches or gravel in the bottom are not clean soil and do not count toward it. Soil settles and breaks down, and above 400 ppm EPA asks for fresh clean soil and compost every year.
A 4 × 8 ft bed, measured inside, takes 42.67 cubic feet of soil at 16 inches: 1.58 cubic yards, or 29 bags of 1.5 cubic feet. Open it in the soil calculator to change the size.
Working the garden and preparing the harvest
These precautions come from EPA’s page unless Maryland is named, and apply at every level.
- Wear gloves, and wash hands, toys, tools and clothes after gardening.
- Take shoes off at the door, use doormats, store garden tools outside living areas and clean floors often.
- Mulch bare soil to keep dust down and soil off the crops.
- Keep the soil near neutral: EPA gives pH 6.5 to 7.5 to limit how much lead plants take up; Maryland gives 6.0 to 7.0.
- Site the garden away from old painted buildings and busy roads. Maryland names homes built before 1940 with painted wooden walls.
- At harvest, discard the outer leaves of leafy vegetables, wash everything and peel root crops. Maryland suggests rinsing the soil off outdoors.
- Maryland advises parents of children under 6 who live where the soil is contaminated to consult their physician, who may recommend a blood lead test.
Try it with your numbers
Open the raised bed soil calculator with this guide’s bed filled in, then change any figure to match yours.
Open the raised bed soil calculatorReferences
- Healthy Gardening Practices to Reduce Exposure to Lead-Contaminated Soil, US Environmental Protection Agency.
- Lead in Garden Soils, University of Maryland Extension.
- Updated Residential Soil Lead Guidance for CERCLA Sites and RCRA Corrective Action Facilities (January 2024), US Environmental Protection Agency. Checked October 9, 2026.
- Residential Soil Lead Directive for CERCLA Sites and RCRA Hazardous Waste Cleanup Facilities, US Environmental Protection Agency. Checked October 9, 2026.
- Growing Vegetables in Raised Beds, University of Maryland Extension.
- 16. Vegetable Gardening (Extension Gardener Handbook, AG-831), NC State Extension.
- Creating Raised Bed Planters, Iowa State University Extension and Outreach.