Can You Use Pressure Treated Wood For Raised Garden?

Pesticides and other chemicals have been used to treat pressure treated wood in order to stop fungi, insects, and rot from damaging the wood. The wood’s compounds may erode into the soil and then be absorbed by plants. More toxins are absorbed by root crops like potatoes and carrots than by leafy vegetables. For raised vegetable beds, pressure-treated lumber is not suggested.

What Is Treated Lumber?

Wood that has been thoroughly treated with chemical preservatives is known as treated timber. As opposed to untreated wood, these preservatives aid in extending the wood’s intended usage.

Lumber is shielded from fungi, termites, aquatic organisms, and structural breakdown by a number of preservatives.

Never utilize creosote-treated railroad ties. This wood has a dark color and a petroleum scent. Extremely harmful chemicals were utilized to cure this wood.

It might be difficult to detect if recycled wood has had preservative treatment. The color and smell of pressure-treated lumber are identical to that of untreated wood. It is advisable to utilize repurposed wood for flower-growing pots rather than vegetable ones.

Can You Use Pressure Treated Wood For Raised Garden?

Cedar is the most secure type of wood to use for vegetable container gardening. It costs a lot yet is durable and long-lasting. Other untreated hardwoods can be used to construct raised beds safely, but depending on the wood, your project will rot and warp in a few years.

Durable lumber that resembles wood is known as plastic lumber. Manufacturers employ different polymers and composites to create their products. They might or might not be safe for food.

Additional Protection For Your Plants

Planting the edible crops closer to the raised bed’s center will reduce the possibility that chemicals from the lumber will be absorbed by other plants grown in the same raised bed. The raised bed could also be lined with plastic.

Before adding soil, a strong plastic liner can be placed inside the wood frame to ensure that no toxins from the wood can leach into the soil and be absorbed by the plants.

Your plants will be protected from harsh temperatures by it as well. A nonporous plastic liner will prevent water from adequately draining out of the soil, so opt for sheet plastic or pond lining instead.

For raised beds, there are materials other than pressure-treated lumber available if you’re still concerned about the security of your plants. According to Lowe’s, untreated lumber is plant-friendly yet prone to damage from insects, fungi, and rot.

Some woods, including cedar, redwood, and some varieties of oak, are naturally resistant to rot, but they can be more expensive to purchase.

Bricks and concrete blocks are additional options, as are synthetic or composite lumber, however there hasn’t been much research on how safe these building materials are for food plants.

Do Plants Absorb The Preservative In Elevated Garden Frames Made Of Pressure-Treated Wood?

Although testing have demonstrated that the quantity of preservative leached from the more recent PT wood products is so small that it is essentially unnoticeable, it is true that plants can absorb these preservatives.

The new preservatives’ impact on lower plant life, like algae, is the main hazardous issue expressed thus far. However, most homeowners wouldn’t be affected unless they lived close to a lake.

How Safe Is Pressure Treated Lumber?

If certain aspects are taken into account, pressure-treated wood is quite safe. These consist of;

To stop the chemicals from leaking into the soil, plant the crops away from pressure-treated wood walls.

putting on a sealer to guard against CCA exposure. Oil can be used to seal things. This shields people from stains and provides protection.

Is It Safe For Growing Food?

Despite being secure, pressure-treated wood is not advised for use in gardens intended to raise food. If an impermeable liner is positioned between the wood and the soil, it can still be used.

To lessen the exposure of food crops to pressure-treated wood, the following actions are taken. Planting should be done with the crops away from the garden bed walls. By doing this, the preservative won’t seep into the soil.

The garden beds should be lined with plastic sheeting. Between the plant roots and the pressure-treated wood, they build an impermeable barrier.

Before eating, peel root vegetables for further security. This is so because plant parts other than the roots contain more copper. Copper traces are removed through peeling.

Exposure To Cca Can Be Prevented By Using A Sealer

In older decks with CCA and in newer decks with preservatives, studies have shown that the use of a penetrating oil finish can limit or even eliminate exposure.

Therefore, it is advised that an oil finish be applied as necessary to any pressure-treated surfaces that come into touch with people. Studies have shown that exterior paints and stains that are not completely absorbed into the wood do not provide the same level of protection.

At least every few years, or when water no longer beads on the wood surface, they should be recoated.

For garden frames and rough constructions, some manufacturers are adding a water repellent to the preservative, which would make the need for a sealer less critical or unnecessary. 

However, for decks exposed to abrasion and sunlight, routine sealing is still a good idea to preserve the surface.

What Is CCA – Treated Wood?

This wood preservative contains varying levels of chromium, copper, and arsenic. Timber is impregnated with CCA treated wood to shield it from microbiological and insect attacks. The treated wood acquires a greenish tinge as a result.


Chromium, copper, and arsenic-containing preservatives are used in CCA pressure-treated woods. They provide protection against microbiological assaults, termites, and even structural concerns.

Vegetable gardens can use pressure-treated wood as long as safety procedures are taken.