heres a pic

Onions are shallow-rooted plants, they should be fine in that bed this year. The carrots, it depends on what kind of soil is lower down, but transplanting them won't work. Was it mine, I'd just leave things as is for the current crop.

Some erosion is just a fact of life with raised beds. And if you have a lot of organic matter, it will settle as it decays. You don't want to firm it down til it's like concrete, and you want to allow for drainage.

Is the soil coming out the bottom or between the seams of the two boards? My beds are on a slope, though they are built of concrete blocks.

My concrete blocks are set about an inch or two below soil level in shallow trenches filled with gravel, and though they are not mortared, they do fit together pretty tightly. I have not had this problem with erosion.

I should think that if you can set the bottom board down into the ground a bit, preferably with gravel underneath to provide water with a way out, and/or close the seam between the two boards (perhaps with some caulk?) that you might be able to solve this problem, at least for now.

I have taken down walls of my beds a time or two to do other minor repairs, and amazingly, the soil has not moved. I waited for a couple of days after a rain, so that the soil was firm. Then I removed blocks, made repairs, and then put them right back up.

it appears that all the erosion is happening from the bottom, not between the two boards.

I think if you have room, you might be able to fix the problem by mounding up soil or sand or gravel outside the box. I always partially set my raised beds in the surrounding soil, and I make them from one piece of lumber. I have never had a problem like that. I have had the beds sort of shrink down a bit due to not being packed in, but I haven't had soil wash out. I also make sure my beds are level at the top, which probably helps.

Hope that helps.

--McKenzie

You can pack the soil real hard around the boards, bot from inside and outsid. Also, add some more soil where it has been eroded. ReTransplanting onios it easy. It would only require time. Onions are tolerant of transplanting.. We have seen onion sets on the shelves of nurseries sitting for weeks, without water, without soil. Remember that onions bulbs should be barelt under soil.

Just a curiousity ; It seems to me from the picture that you have wasted a lot of area by planting the onios too far apart, I would plant maybe twice as many. Lets look at it this way: What is the diameter of the largest onion? 3 inches? lets give it another 3" room. So you can space your onion seedling at 6" apart.

Dig a 6" deep trench directly outside the bottom board & install flashing. Then put the dirt back. That's what I did & it has worked for 2 years. :)

Thanks everyone for your replies :)
Deborah-SC - What is "flashing"?

Seysonn - in the past two years, my onions have been real small, so I asked the guy at the nursery why, and he said I've been planting them too close together. So I moved them farther apart this year.

Just nail/screw it to the bottom 2 inches & let four inches hang down. (Hence, the trough). Then fill the trough back in with dirt. Take care!

Here is a link that might be useful: Flashing

i'd suggest let the onions grow and when you pick them top up the whole bed but at that end use some timber or other to place along that area down into the base soil, then pack new dirt in behind it, me if i had some say 50mm sized stones around i'd just put them there and fill soil over the top.

len

Here is a link that might be useful: lens garden page