In our second year, I used a mix of the surviving trays and toilet paper rolls - save the rolls once you're done with the toilet paper. Then in the spring, fill them tightly with potting mix, water thoroughly, and plant the seeds (like here). Once the time comes to transplant, pop the whole thing in the ground and cover. The cardboard will disintegrate over time. This approach was pretty good for things that don't like their roots disturbed (carrots, peas). However, the rolls got moldy and unpleasant over time, and roots escaped sideways into the tray, resulting in a bit of a struggle during transplanting time.
This year I came across the technique of air pruning, the approach where some of the plant's roots are exposed to air, after which the tips die and the root branches (here's more detail: air pruning). The result is a branched, healthy root system, with no root-bound plants.
There are quite a few different containers and approaches to this, from fabric pots, to planting in shopping bags, to nursery-quality air pruning pots. To start the seeds, I tried two different approaches - one making seed starter pots out of newspaper (instructions here: newspaper pots), and one using net cups, following the advice of the air-pruning guru, Larry Hall (here is his FB page; note that it's a closed group and you'll need to be added by the admin, and his YouTube channel).
I bought 100 cups on Amazon (net cups). They're fairly sturdy, and should last quite a few years, especially if I'm nice to them. I made another 100 or more newspaper cups to accommodate the rest of the starters. Silly of me, I didn't do a proper control, where you would plant the same seeds in the two growing containers, to see which one does best. However, so far most of the net-cup plants did much better than the newspaper ones. I did not expect such a difference (and perhaps that's why I didn't do the control bit). But I know that I will be buying another 100-200 cups for next year's season.
One extremely helpful tip that I read about this spring was to use aluminum foil as a reflective surface between the seedlings and the rooms. When growing seedlings on windowsills, they end up bending towards the light source. To reduce bending, the plants need to be turned once or twice a day, which is a chore if you have quite a few of them. The aluminum foil does two things: 1) it doubles up the amount of light the plants receive, which results in shorter, sturdier plants, and 2) it prevents the plants from bending. As a result, the plants only need to be turned once a week, if that - I haven't turned many of my seedlings in weeks now, and they're only slightly off-center...
Hopefully these help someone out there!
Have a great growing year
I found my plants in the coir blocks did a lot better than the ones I planted in my homemade newspaper/cardboard tube pots as well. Identical varieties in each type of pot:
Oh, forgot to mention that the guy advocating the net cups (Larry Hall) uses this mix for starting and growing plants:
2 five gallon buckets full peat moss
1 five gallon bucket Well rotted horse manure or compost or worm castings
1 and 1/2 cup Garden lime
1 large coffee can full of perlite
1 handful of Epsom salts
And you can add your own rock dust, bone meal, blood meal, etc
I used garden soil instead of manure (and used 2 buckets of soil instead of 1 bucket of manure, to increase volume), since the manure we have on hand had insect eggs, and I wasn't comfortable with it. They tell you to not use 100% soil though, since apparently it won't wick moisture when you water from the bottom...
I tried using Gutter Guards (even cheaper at Dollar store) pots I made. However, my biggest problem is moisture. They dry out sooooo quickly. I can't keep them watered enough.
Same with soil cubes btw. I really believe air pruning is the way to go but I can't figure out the water issue.
Did you have that problem? What do you do to keep them soil moist?
S Usvy wrote:If you have them in large enough trays, you could try to go the self-watering route, modifying the kiddie pool approach (sorry if it sounds crazy, here's an article with pictures kiddie pool setup) for full-size plants - have a tray with a flow valve in it, hooked up to a tap. As the container dries, the valves opens and adds water... You'd have to play with level of pots vs. level of water, so that the plants don't constantly have wet feet, but with a large enough number of plants, it could be less work than manual daily watering.
Cool thanks for the link. Kidie pool doesn't sound crazy. I have one already. I am just manually controlling the water which is a pain!
self watering containers
"watering reservoir"? I am thinking of something like for watering your dog/cat/chickens for
extended periods that release water as needed, as the water is used... like when your dog
takes a drink... lowers the water level, which allows some air to enter the bottle and results
in some release of water, until the water closes the air gap and stops the release.
Theoretically this could be scaled up to almost any size. Just a thought.