In some places, it’s time to get seeds started for this summer’s outdoor garden. Cold climate dwellers would be jumping the gun to start propagating now, unless they’re aiming for beating cold weather for a good tomato harvest. But as winter drags on the urge to get growing sets in, and it’s a great time for planning just how you’re going to get your seedlings going in anticipation of planting out.
Recycling is one way of reducing the cost of getting the garden going no matter where you’ll be harvesting – off the patio, on the balcony, or from a plot in the ground. While peat pots are cheap, most people have some household waste that can make seed starting containers.
The paper variety only. Could you start seeds in a styrofoam egg carton? It’s not advisable. And there are drawbacks in either type.
Firstly, consider how much smaller the cups of an egg carton are compared to those in a purchased seed starting tray. Starting tray cells are also about half the capacity of the sections of those in a tray pack used for growing plants in flats, like when you buy petunias or veggie plants from a greenhouse. Why does it matter? The most important part of your starter plants is hidden inside the cell beneath the surface of the seed starting medium.
So… plants started in egg cartons will not have much of a root system. At least with paper egg cartons the roots can grow through the bottom, which is bad unless they’re sitting on something saturated with moisture at all times. If cold weather hangs on longer than normal, their root systems will start growing up out of the potting mix where drying will quickly become an issue, along with other issues any grower wants to avoid.
Secondly, egg cartons will not drain. If you do decide to use them, do yourself a favor and create drainage by poking holes in the bottom of each egg cup.
To get really robust starter plants for your summer garden outdoors – use something much deeper than egg cartons. Your eventual harvest counts on a well developed root system, which is not going to happen in an egg carton.
Newspaper or phone book pages only. Copier paper, inkjet paper, and glossy paper like is used in catalogs and magazines has stuff on it you don’t want food plants absorbing, nor do you want it in your garden soil. Yes, it breaks down, but more slowly as it is treated to slow it’s decomposition, and can contain dioxins. You shouldn’t use office papers or magazine pages for composting either, or colored paper and anything printed with colored inks. the last two will contain heavy metals, though soy inks do not. Something to remember for making compost too.
Rolled newspaper seed starter tubes are biodegradeable. You don’t want a bottom in this kind of plant container. Wet newspaper does not drain well at all. If your seed pots can’t drain, your seeds or fragile seedlings will rot. Seedling death by root disease or drowning is also an issue with improper drainage.
What size should your newspaper seed pots be? How long will the plants have to stay in the starter cell? Jumbo cell starter trays measure 1.75″ x 2.25″ x 3.5-4″ deep. A small tomato paste can or average spice bottle would make a good mold. If you make them too little, you’ll be potting up to larger containers before you know it.
Paper towel and toilet paper rollers are both candidates for seed starting container materials. The best part here is you don’t have to mess around with molding them, not to mention they are biodegradable. Just save them up over the winter, slice the proper length with a utility knife, and start sowing your seed once the seed starting mix in in place.
I’ve seen some images suggesting that a bottom should be made by creating flaps and folding them over. Totally unnecessary. Good roots will hold the soil in place by the time the young plants are ready to go into the garden or patio containers. The flaps could make the starter tubes easy to tip over unless they are perfectly level… why waste all this time and tubing?
Do make sure you’ve cut them as level as possible. Don’t make them too short or you’ll have issues like with egg cartons. A toilet paper roller makes only 1 starter pot, but no cutting is needed as they are 4″ tall already. Paper towel rollers are 11″ long, and cut into 3 equal sections give you growing tubes that are 3.66″ deep, which is perfect.
If you don't find her at the desk - check the gardens. When not writing and weeding, she enjoys a good book, painting junk furniture, and blending the harvest of heirloom tomatoes and chiles into salsas.