8 Easy Ways to Repair a Raised Garden Bed So It Lasts Much Longer

Whether your raised garden is built from wood, stone, metal, or cinder blocks, raised bed gardens need regular maintenance to keep them looking trim. Sometimes, this can involve a minor touch-up, such as adding a bit of fresh soil, but at other times, these maintenance tasks require more elbow grease and finesse. Here are some of the most common ways raised beds start to fall apart, along with tips for fixing these issues so your raised beds last longer.

1. Bulging or Bowing Sides

One of the most common issues gardeners encounter with raised beds is bulging or bowing raised bed walls. This occurs as the soil inside the raised beds settles and exerts pressure on the sides, which can potentially cause the sides to collapse if action is not taken.

The Solution:
Prevent raised bed sides from bulging by choosing metal raised bed frames or installing a 2×4 or metal rod crosspiece across the center of wooden raised beds. Installing metal corner brackets and keeping beds under 6 feet in length can also help, as longer beds are more likely to bow.

If an existing bed is bowing out, add a cross piece or drive rebar rods into the soil along the exterior of the bed. This keeps the bed from sagging further. However, you might need to temporarily remove the bulging boards and excavate some of the settled soil if you want the beds to look perfectly straight again.

2. Rotting Boards

Raised bed frames made of wood can start to rot, causing the wood to feel mushy, flaky, or collapse entirely. This is especially common if the beds are made of untreated wood, like pine ledger board.

The Solution:
Avoid rot issues by selecting metal raised bed frames or building wooden beds from rot-resistant wood, such as cedar. However, if you don’t want to pay a high price for raised beds, you can use an inexpensive ledger board and plan to replace the boards every few years.

The good news is that soil typically stays in place if you remove just one side board at a time, which makes it relatively easy to replace rotted boards as needed. Remove any hardware holding the board in place, take away the rotted board, and install a fresh board of the same size. Painting or staining wooden boards with a food-safe sealant can also help them last longer.

3. Soil Erosion or Washout

If you notice that the soil level in your raised beds looks lower, you’re probably not imagining things. Soil commonly washes or erodes out of raised beds due to heavy rain and wind, and it’s particularly common if raised beds are built in a poorly draining spot or on a sloping location.

The Solution:
Avoid most erosion issues by building raised beds on a level and well-draining location and leaving several inches of space between the top of the soil line and the top of the raised bed. If the soil has started to wash away, replace it with a high-quality raised bed soil mix and consider adding mulch, cover crops, or ground-covering plants on top of the soil to prevent further erosion.

4. Sinking Corners

Raised bed corners can start to sink or become uneven over time due to erosion. Like washed-out garden soil, this is more likely to occur if raised beds are built on an uneven surface.

The Solution:
Installing raised beds on level ground can prevent the corners from sinking. However, if the raised bed corners have started to sink or rise above the soil line, you can dig out the sunken corners and add tamped-down gravel beneath the uneven corners to prevent them from moving again. While you’re at it, you may also want to sink a few angled rebar rods around the moving corners as well.

5. Pest Damage

Pest damage from termites and other wood-eating insects can resemble rot, making it difficult to distinguish between the two. While pest damage and rot can both cause wooden raised beds to get flaky or feel squishy, pests can drill small holes in wooden raised bed frames or heap mounds of loose soil in or around the garden.

The Solution:
Carpenter ants and termites are the most common types of pests that damage wooden raised beds. Companion planting with fragrant herbs that deter insects and choosing metal raised bed frames can help reduce some pest issues. You may also want to apply repellents, such as cinnamon or peppermint oil, to keep these bugs at bay.

6. Missing or Rusted Hardware

Wooden raised bed corners are often secured with nails or screws and sometimes with metal corner brackets. These hardware items can sometimes rust or fall off the bed entirely, especially if the bed frame starts to rot or flake. Unfortunately, if enough hardware is lost, the integrity of raised beds is compromised, making them more likely to collapse.

The Solution:
Check raised bed structures periodically and replace missing or damaged hardware as needed. If you’re having trouble removing rusted screws, you may be able to remove some of the rust with steel wool and a vinegar soak or simply replace the rusted screws with new ones. That said, if the raised bed frames have also started to flake or rot, you may need to replace entire boards instead or install heavy-duty corner brackets for added strength.

7. Flaking Finish

Stained or painted raised beds may start to peel, flake, or look drab over time. This is sometimes only an aesthetic issue, but it can increase the chances of rot if waterproofing material flakes away and exposes the untreated wood beneath.

The Solution:
Using naturally water-resistant building supplies, such as metal or rot-resistant wood, can help you avoid the need to paint and finish raised beds. If you have painted raised beds that are already looking bedraggled, remove the old finish with sandpaper or steel wool and apply a fresh coat of food-safe and water-resistant paint or stain every year or so.

8. Poor Drainage

Raised beds can become soggy or develop pooling water if they’re built in a poorly draining spot or filled with overly dense soil. Drainage issues of this sort can make it difficult for plants to grow, and they also increase the likelihood of soil washout or raised bed rot.

The Solution:
The best way to prevent drainage issues is to locate raised beds in a well-draining, level location and fill them with a raised bed soil mix that includes plenty of sand for optimal drainage. Unfortunately, standard garden soil is too dense for raised beds and can lead to soil compaction and general sogginess.

If your raised beds are already installed and draining poorly, grading the soil around the beds or installing small drainage ditches can improve drainage. You can also mix more compost into the soil to enhance drainage or switch to growing plants that tolerate wetter conditions, such as watercress or cardinal flowers (Lobelia cardinalis).