Some stunted cactus seedlings

[keithp2012]

I have some two year old cactus seedlings. Most are growing normally and are a nice size, but 3 have stopped growing since a year ago and remain the size of a pea, they only plump up with watering but don't grow any more. Color looks good.

I've even repotted them and given the best care and fertilized them and they remain alive but are dwarfs. Is this just a genetic defect? Do you think they will continue to live but not grow any further?

[mdpillet]

They'll grow at the their own pace when they're ready. Repotting may not have been the best solution in this case - takes time to regrow hair roots.

[keithp2012]

They'll grow at the their own pace when they're ready. Repotting may not have been the best solution in this case - takes time to regrow hair roots.

They had very long roots, when I removed them I scooped from below, no roots were damaged. The cacti plumped up days after transplant the nursery had hard compact soil. Transplant didn't do harm.

[kristian_Fossmo]

I believe that sometimes growth is directed to the parts underground, if it is taprooted species they may just focus the growth to the taproot. I had a Gymnocalysium gibbosum that stayed really tiny for a long time. I treated it like an small seedling, overwatered it and killed it just a week ago. Luckily I have another little bigger in an different pot that still lives and receives less water. Some species just grow slow, probably some genetics to it also among the same species. Maybe try to change some other factor just a tiny bit, less/more light, warmer/coolder...

[hegar]

First of all it is important to know, whether or not all the seedlings are of the same genus and species. Some cactus just do grow more quickly than others, even if they do have the exact same environment, light, fertilizer, water, etc..
Then, even if they are of the same genus and species, there are genetic variations between individual plants. Some will be more vigorous than others.
As long as the "laggards" do look healthy, I would not worry about them.

Harald

[keithp2012]

Here is one of the small seedlings, it's siblings are 3x as big and round, where this is very oddly shaped.

[adetheproducer]

It's growing so just be carefull with watering and be patient. I got a couple of seedlings which stalled for a good year like this but this year have shot up.

[SoilSifter]

Might some cacti need a Winter dormancy period? I have some Peniocereus seedlings that aren't growing. I suspect they need a Winter season before they will grow in the Spring but my Winters are too cold for them and the inside of the house might be too warm.

[keithp2012]

It's growing so just be carefull with watering and be patient. I got a couple of seedlings which stalled for a good year like this but this year have shot up.

I see its growing but odd how tiny it is for almost 3 years old! It's siblings are the size of oak acorns. Also another weird trait is growing tall and not wide even though it's given plenty of light. Also, the bottom half is purple and the top is black, it's split coloring! I'll try my best to keep it healthy!