The question is, At what size should you put a vegetable seeding into the ground or a bigger pot? The answer is, At any size before the seedling is rootbound. Rootbound means the roots in the container are crowded and circling, especially at the bottom.
Let me illustrate with photos. Above is my cart of vegetable seedlings, as of yesterday. I caught a cold last week so some of the vegetable seedlings I would have transplanted earlier were left in their containers longer than ideal while others I suspect still aren’t ready for transplanting.
Let’s look at some individual plants. First, a Jericho lettuce plant.
Now I pop the plant out of its container to look at the roots.
Perfect timing. This is what I want the roots to look like when I either put the plant into a bigger pot or into the ground. The roots have filled out the volume of soil, but they aren’t too crowded yet.
Second, a Space spinach plant.
Above ground the plant seems small . . . and the roots?
Not ready for transplanting. There is still soil for the roots to exploit, as you can see by some crumbling onto my palm. A full rootball will hold together.
Now you can transplant this spinach plant. If you’ve got a spot in the garden ready for it, and you’ve got the time to do it only now, go for it. But if you want to grow it in this container as long as is healthy, then you could wait another week or so.
Third, this Tendersweet cabbage plant.
Pretty big plant. How about the roots?
There are way too many roots for that volume of compost. All I see are roots. The plant needs access to more compost or soil. It should have been put into a bigger pot or the ground last week (while I was nursing my cold).
Did you notice the yellowing lower leaves?
That indicates that the plant is no longer getting all of the nutrients it needs from the soil/compost that its roots are in. It needs more. The plant is being stunted.
Two more plants. But since I’ve already shown and explained when I like to pot up or transplant seedlings, I’ll let you answer these ones. First, my onions.
Let’s look at the roots of the biggest plant.
Pot up or plant now, or wait? Why?
And finally, my peas:
The roots of the biggest plant.
What do you say? Ready for potting up or transplanting, not ready yet, or waited too long?
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