Seedlings - How big is too big?

Post Reply
zeuspaul
Reactions:
Posts: 1557
Joined: Sat Mar 14, 2020 9:24 pm
Location: San Diego County

Seedlings - How big is too big?

#1

Post: # 40170Unread post zeuspaul
Fri Feb 05, 2021 11:35 am

I have been sequencing my starts. The first ones I started in early January are doing very well and look like they will be ready to plant in the garden by mid February in a couple of weeks. But mid March or early April is as soon as I think I should plant depending on the 10 day forecast.

This is my first year with grow lights. In the past I carry them inside and outside every day. They get 16 hours of light including 5 hours of sunlight. If I cut back on light can I slow them down? How much is too little?

I still have time to replace them with new starts but want to try and save at least a few of these if I can. I can pot-up the 2 x 3 inch pots to 4 inch but I fear they may still get too big. I could try going to 1 gallon pots but I only have room for a limited number of those. How big of a plant is considered too big? I could take and root cuttings but would the plants from cuttings be as good as the ones from seed? Is the best alternative to just start with new seedlings?

User avatar
root_grow
Reactions:
Posts: 136
Joined: Fri Dec 13, 2019 12:21 pm
Location: Coastal Washington

Re: Seedlings - How big is too big?

#2

Post: # 40178Unread post root_grow
Fri Feb 05, 2021 1:36 pm

Last year in the early stages I thought I'd be growing in a slightly warmer place and wanted to try getting an extra early start as an experiment, so I started seeds 10 weeks ahead of when I thought I'd plant them out (started in Feb for early April transplant). Then life got crazy, we ended up moving somewhere a bit colder, and garden ground wasn't even ready until May. So they sat in their little 16oz solo cups in my landlady's solarium until mid-May. They were around 2' tall and definitely required extra care not to break them when I could finally transplant, moving them in and out every day was definitely not an option, but they took off super fast once they finally got in the ground. I read all over the internet that they were suffering, they were too big and root bound, setbacks, etc, etc, but they were green and healthy, and grew and produced just fine. I also started 12 plants around mid March, the usual start time around here. My monster early plants all grew and produced far better than those (except Tundra ;) ). I don't know if that's climate related since it's so mild where I am now, but it was very useful to me and very much not in line with common guidance, so just thought I'd share.

2 (out of 100!) snapped at transplant and I tried to save them by rooting the tops. Those plants grew normally too, it was just too late in the season by then to get much production. It sounds like it could be a good option for you, maybe some others here have more experience with that.

I wouldn't mess with the lights because making them leggy at this point would be counterproductive. Cold would slow them down more, if you could find or create a place colder than room temp but above 40. I think it might also help to have them in something taller than the typical 4" pot to give them just a little more root space while they wait. That's why I like the solo cups, but plastic bottles or milk cartons or similar could work too and take up less space per plant than gallon pots.

Gardadore
Reactions:
Posts: 841
Joined: Wed Dec 11, 2019 12:15 am
Location: NE PA zone 6

Re: Seedlings - How big is too big?

#3

Post: # 40187Unread post Gardadore
Fri Feb 05, 2021 2:55 pm

Every year some seedlings get taller than others. I am a great “staker”! To keep the stalks from breaking I insert BBQ bamboo sticks and tie them to the stalks with Velcro. If they get very tall then I use thin two foot bamboo sticks.
It makes moving them much easier because if the cup tips over the plant won’t break. When I plant I go as deep as possible and again use bamboo sticks with Velcro. Last year we had a very cold spring so seedlings were transferred out later than usual.
This year I have saved a lot of the large yogurt containers for seedlings that outgrow the Solo type cups. I did that with a couple of seedlings last year and they developed much thicker stems as a result.
Last edited by Gardadore on Sun Feb 07, 2021 2:48 am, edited 1 time in total.

User avatar
Cole_Robbie
Reactions:
Posts: 1432
Joined: Tue Dec 10, 2019 11:58 pm

Re: Seedlings - How big is too big?

#4

Post: # 40219Unread post Cole_Robbie
Fri Feb 05, 2021 8:05 pm

Normally the issue with clones is that you are also cloning whatever diseases the mother plant carries, but in your case, you are so early in the year that shouldn't be a problem.

zeuspaul
Reactions:
Posts: 1557
Joined: Sat Mar 14, 2020 9:24 pm
Location: San Diego County

Re: Seedlings - How big is too big?

#5

Post: # 40302Unread post zeuspaul
Sat Feb 06, 2021 8:14 pm

If I top the plants will I slow root growth? Once I purchased plants on sale and found out when I planted them that they were extremely root bound. Those plants never did well.

What about topping them once they start looking too big and also removing them from their pot and pruning the roots? I would end up with two starts if I also clone/root the cutting. Would I replace in the same pot or go larger? I like my smaller square pots because I have more room for them in my trays and under the lights. I have never pruned roots. Would I remove most of the soil first? or just trim the roots back with the soil in tact?

I have already started repeats from seed and I will end up with way more than I have room for in the garden but that is better than not enough. I could give some away but I am not willing to give away my pots which I reuse and have had for many years.

mama_lor
Reactions:
Posts: 226
Joined: Mon Feb 01, 2021 7:44 am

Re: Seedlings - How big is too big?

#6

Post: # 40429Unread post mama_lor
Mon Feb 08, 2021 2:17 am

Yes, cold will surely slow them down better than anything, cold and somewhat lower light. The problem is pythium will thank you for the ideal conditions. Rootboundness is very related to watering, the one you buy in the store have been at some point severely dry, and that makes the roots grow even more. A wet medium will keep it much less problematic. But again, problems with pythium, but overall if the plants are already bigger, this shouldn't be a maybe such a problem.

Post Reply

Return to “Seed Starting”