[Howard]

I was going to ask this on the 'Nipping out side shoots' thread but I didn't want to take it off on yet another tangent, so...

When I potted on my tom seedlings into 3" polybags, even though they weren't at all leggy, I deliberately sank them almost to the seedling leaves so that they would produce adventitious roots.

This is the first time I've done this and I'm convinced it has helped, they're the healthiest tomato plants I've grown yet. 

So, as I will soon need to pot them on again, can I carefully cut off the cotyledons, let the wounds heal and sink the stems below this point when I pot them on? Will they produce more adventitious roots from the stem above where the cotyledons are?

Many thanks in advance,

Howard

[DD.]

I would not go chopping about young plants. This could lead to infection. If you feel you need to pot them on deeper, why not just bury the cotyledons?

[Howard]

...If you feel you need to pot them on deeper, why not just bury the cotyledons?

This would surely run the risk of infection by rot, no?

Would I be right in assuming you don't feel there's anything to be gained by me doing this?

[DD.]

It's more natural than cutting them off.

I plant the seedlings on the first pot like yourself, as deep as possible.

The next pot on is into their final pots when about 6"-8" high. By this time the cotyledons have dropped off naturally and I just plant an inch or so deeper.

[Howard]

Thanks for your thoughts DD.

[Kristen]

When I prick out I plant most things up-to their cotyledons (particularly if they have got leggy in the propagator / windowsill.

Toms will root from their stems, but I don't transplant them "deep", but I do leave some space in the pots so that I can add a little compost.  In 12" final pots last year I added about 1" of compost a month or so after they were potted up - but they didn't seem to be showing any roots higher up than that, so I didn't feel the need to add any more compost.

[Howard]

...but I do leave some space in the pots so that I can add a little compost...

I did think this might be another way to go about things. 

...In 12" final pots last year I added about 1" of compost a month or so after they were potted up - but they didn't seem to be showing any roots higher up than that...

I have noticed that the stem below the cotyledon point is almost a plum colour, and moves through to green over the next two or three inches. I wonder if this has any bearing on what you've found?

Howard

[Kristen]

I get some little nodule-y things appearing low down, which seem to turn into roots if encouraged with soil.

I've got some at the bottom of my Cue plants too ... but they so hate getting their stems wet I'm not going to risk planting them deeper - in fact re-potting them last night from 3" to 5" I sited the original 3" root ball fractionally higher than the new compost.

[lucywil]

for those of you, like me, that have no idea what a cotyledon is I just googled it and its the correct term for what we know as the seed leaves!!!

[DD.]

And what were you up to when you did biology at school?

[lucywil]

And what were you up to when you did biology at school?

Good question! i have a GCSE in biology as well!! thing is my memory is not what it used to be

[jolly jen]

for those of you, like me, that have no idea what a cotyledon is I just googled it and its the correct term for what we know as the seed leaves!!!

thank you i did wonder ,was just about to goggle,,
simple and plain,,,,,,,it helped

[Howard]

UPDATE


In the end I decided to cut off the cotyledons. The decision was kinda made for me, really, as most of my toms were throwing out side shoots and these needed nipping out. So, armed with a clean scalpel, off they came.

I gave them three days for the wounds to dry and potted them on into 5" polybags, about ¾" down. Six days on and they're looking just fine. 







As an aside, I decided to save the side shoots and planted them up, which I've not done before. Some of them (the Piccolo especially) were far smaller than is ideal but I'm oddly hopeful.

I guess I shall just have to wait and see!