Backyard Aquaponics
A place to discuss aquaponics

Hi all, this is kind of a novice question, but I was wondering if there were certain methods/techniques for safely transplanting seedlings from a grow tray into the growbeds. My growbed media is pea gravel (approx. 5-15mm size) and it's pretty gnarly and jagged.

My partner, who is much more of a plant guy than me, thinks that transplanting them will irreparably harm the roots. But know it can be done. I saw someone say that it's good to spray seaweed extract on the roots before transplanting. This guy also sprayed the seaweed extract on the leaves too. I was not aware that spraying the extract on the leaves would do anything, as I thought it was only effective on the roots, but he was also spraying his whole system this way (leaves). So is this normal? (Remember, I'm not a plant guy, haha).

I'm transplanting lettuce and batchoy into barrel growbeds.

(Also, as a side question, the water level in my F/D system floods about an inch or so above the gravel level. Should I lower the water level the the gravel level? Or even lower? And if so, why?)

Thanks for all the help!

First off, lower the water level to about 5cm below the gravel. You'll have algae problems, and any higher and you'll go through more water than you need to, too high and the plants will rot.

I don't think spraying the roots with seaweed will do much, the water will wash it away, it's good to add to the system, but spraying the plants won't do much.

I have jagged media too, never had a problem. I get a bucket of water, dunk the roots in and wash off the soil off. Use a little trowel to move the media to the side, put the seedling in, and backfil with the media.

That's it.

Great, thanks a lot for the advice.

Now I'm a little concerned with my water level. I've adjusted it to where it now just barely covers the gravel, not exceeding by much at all (maybe a mm or 2). Going through excess water isn't really a concern for me right now as my fish tank is WAY disproportionally too big for the amount of growing space (long story), but I am concerned with plant rot.

Do you think that a water level that is equal too or just BARELY above the gravel will rot my plants?

Spraying the leaves does work, plants absorb moisture and nutrients through thier leaves in the same way as we do through our skin.

Columns technique will work well and probably be the most used technique. If you have alot of plants to plant and cant afford to "dig holes" because of media piling ontop of other seedlings, then the way i like to plant (and harvest) is to flood the bed well above the media so it becomes a lot lighter and is less likely to grip onto each other, this allows you to move the media much easier and on some of the lighter medias, allows you to simply hold the plant roots and plunge your hand into the media, then holding the plant stem to remove your hand.

Yes unless the water is lower than the media, you will get root rot.
Think of your media as no different to soil, in that plants in soil do not like water to be around thier stem at all times, for a short period after rain is fine, but the water should not be as high as the stem, no matter if the stem starts above or below the media, keep the water at the root level.

@Yavimaya

Thanks for the excellent tip. Ok, I'm gonna have to do some major adjustments now, haha. I really appreciate it