Growing seedlings in planter boxes?

maxjohnson · November 24, 2016

I'm starting 90 seeds this time. I think it's daunting for to be transplanting every single one of them into individual red cups and labeling them all.

I'm thinking just buying small rectangular planter boxes and transplant 6 seedlings in each until they are big enough to put in raised beds.

Probably will cost a bit, but I'm lazy. I don't care if I damage the roots a bit during the transplant.

A cheaper solution are those aluminum foil pans, somehow I'm not a fan of disposable aluminum.

greenthumbomaha · November 24, 2016

If you are starting different varieties and want to know what you are growing, it will be very difficult to keep track in a planter when you need to poke them out to transplant.

Aluminum pie tins for small individual cake servings would make your task much simpler. Don't forget to poke holes in the bottom. I would suggest 6 seedlings per pan, and they come in packs of 4, so there is a cost. I think they are about a dollar for the pack of 4. Easy to rinse and use next year though.

Potting up in red cups is a project. Many of us use 4 X 4 pots that already have drainage holes and can be purchased in bulk at your local hydro store or greenhouse megastore online. Really easy, cheap, and gives great results. They stack nicety in plastic underbed boxes, and you can even water from underneath.

- Lisa

imp · November 28, 2016

I use solo cups, mostly red ones are the lowest $ here. Stack them 8 or 9 deep and use a drill to make 5 or 6 holes in the bottoms. The solo ones have a slightly raised edge when upside down, so holes in the middle area of the bottom drain well.

If one was more organized, could run those cup labels off the printer to sticky labels and just slap them on the cup versus writing on the cups with sharpies. I ~did~ appreciate shorter tomato variety names last spring!

Mine stay in the cups until transplant time.

maxjohnson · November 28, 2016

I think I found a solution, grow bags. They seems cheap enough at $12 for five 5-gallon.

Cole_Robbie · November 28, 2016

You'll get better roots with a series of transplants into gradually larger containers. The roots grow until they hit the container wall, and then go back and fill in the rest of the space. When seeds are planted in large containers, the roots will not fill in all the media as efficiently.

Having said that, I have not done side-by-side experiments to see how much of a difference it makes in yield or overall plant vigor, so I'm not trying to say that anyone's method is wrong.

November 24, 2016	#1
maxjohnson Tomatovillian™ Join Date: Oct 2015 Location: OH 6a Posts: 592	Growing seedlings in planter boxes? I'm starting 90 seeds this time. I think it's daunting for to be transplanting every single one of them into individual red cups and labeling them all. I'm thinking just buying small rectangular planter boxes and transplant 6 seedlings in each until they are big enough to put in raised beds. Probably will cost a bit, but I'm lazy. I don't care if I damage the roots a bit during the transplant. A cheaper solution are those aluminum foil pans, somehow I'm not a fan of disposable aluminum.

November 28, 2016	#4
maxjohnson Tomatovillian™ Join Date: Oct 2015 Location: OH 6a Posts: 592	I think I found a solution, grow bags. They seems cheap enough at $12 for five 5-gallon. Last edited by maxjohnson; November 28, 2016 at 01:20 PM.

November 24, 2016	#2
greenthumbomaha Tomatovillian™ Join Date: Nov 2011 Location: Omaha Zone 5 Posts: 2,514	If you are starting different varieties and want to know what you are growing, it will be very difficult to keep track in a planter when you need to poke them out to transplant. Aluminum pie tins for small individual cake servings would make your task much simpler. Don't forget to poke holes in the bottom. I would suggest 6 seedlings per pan, and they come in packs of 4, so there is a cost. I think they are about a dollar for the pack of 4. Easy to rinse and use next year though. Potting up in red cups is a project. Many of us use 4 X 4 pots that already have drainage holes and can be purchased in bulk at your local hydro store or greenhouse megastore online. Really easy, cheap, and gives great results. They stack nicety in plastic underbed boxes, and you can even water from underneath. - Lisa

November 28, 2016	#3
imp Tomatovillian™ Join Date: Apr 2009 Location: Wichita Falls, Texas Posts: 4,832	I use solo cups, mostly red ones are the lowest $ here. Stack them 8 or 9 deep and use a drill to make 5 or 6 holes in the bottoms. The solo ones have a slightly raised edge when upside down, so holes in the middle area of the bottom drain well. If one was more organized, could run those cup labels off the printer to sticky labels and just slap them on the cup versus writing on the cups with sharpies. I ~did~ appreciate shorter tomato variety names last spring! Mine stay in the cups until transplant time.

November 28, 2016	#5
Cole_Robbie Tomatovillian™ Join Date: Jun 2012 Location: Illinois, zone 6 Posts: 8,407	You'll get better roots with a series of transplants into gradually larger containers. The roots grow until they hit the container wall, and then go back and fill in the rest of the space. When seeds are planted in large containers, the roots will not fill in all the media as efficiently. Having said that, I have not done side-by-side experiments to see how much of a difference it makes in yield or overall plant vigor, so I'm not trying to say that anyone's method is wrong.