What is best container (and size) for seedlings

Hi,

I’ve blown through all my 16oz styro coffee cups that I have used, cleaned and bleached for reuse over the last 4 yrs. I had those left over from about 10 yrs ago, when faced with having to buy about 100+ cups for a committee. It was cheaper at that time to buy the 1000 case lot at Costco, than to buy 5 sleeves of 25 ea. So they got stuck in the crawl space storage, and used occasionally until I got the brilliant idea that this would be ideal for my seedlings. But now I checked on the replacement cost, and todays costs have surely skyrocketed. So now may be a good time to change, but I want to stick to round pots of about the same size–I have about 3 flats worth of approx. 10 oz (actual pots) containers, and the seedlings seem to need just a little more root space-maybe I could fertilize a bit more to compensate. I don’t want to change to square pots because I have approx. 75+ flats of the round carriers/spacers which are so convenient and easily handled. One question I have is -has anyone used the paper based, poly lined, hot cup that has largely replaced styrofoam cups? And do they last? Or does anyone know of a source for the approx. same size as a 12 to 16 oz cup in an actual nursery pot? Anything bigger than 16 oz is going to take up way to much soil for my use, until I pot them up into a gal. (after some initial editing) at the end of the summer. I am curious about the hot cups, because I believe that is what they use at the nearby coffeehouse, and I’m pretty sure they wouldn’t mind me retrieving a few days worth from the trash.

Jackie, are you the American version of the English person on the the show “Steptoe and Son. (collectors of anything). Many years ago we used to go our local race course and reteive the spent " clear plastic beer cups”. It worked great with all sorts of plants. Regards David.

Jackie, I use the 16oz, clear plastic drinking cups from Costco. I like the clear ones because I can monitor the root growth better. They come in a package of 50 for around $10.00. The red ones are cheaper but I’ve found they’re not as sturdy and like I said, you can’t see the roots to see when they need repotting.

I am definately into recycling-esp. of non renewable resources. Tossing away a plastic cup after only one beer? At least have several beers with the same cup, and make the sacrifice of that plastic worth while!

Sounds like I may need to hang out in one of those beer drinking venues.

Jackie, Your welcome to pop over to collect the cups and enjoy a day at the races. B****y health regulations make it one use only for cups. I have placed a linh below so you can choose which meeting that suits for your attendance.

www.racenet.com.au/Mudgee-raceclub-nsw

I have used the coated paper for several weeks with tomatoes or other spring plants but would not count on them for a whole summer. The kind people use for picnics whether clear or color plastic, are a lot more durable and have lasted a whole season. One football game in a decent sized stadium generally yields a full year’s worth (from one or two trash cans).

The clear Costco cups seem to get embrittled by the sun. A few years ago I started making my own pots from 20 oz soda pop bottles. It takes a bit of labor but they last indefinately and stand up to repeated cleaning.

To make a pot from a pop bottle slice the tops off with a razor blade and poke drain holes with a soldering iron. Mine get a spritz of flat white spray enamel which helps greatly to control overheating by sunlight.

My hubby likes ramen noodles for lunch so I buy the kind in the individual styrofoam cups that pop in the microwave. Then I have a nice size cup to recycle for use as rose seedling pots or for veggie seeds.

I once used paper cups, over a decade ago, and have subsequently decided it was a… ah… rotten idea. I haven’t tried it again, and would imagine that some paper cups are of a more durable nature than others. Mine grew a lovely mold on them, as I recall.

Check the type of plastic that cups are made from. Some are more UV resistant than others, though obviously none of them will have the black UV inhibitors in them that commercial pots would have. I believe PETE is pretty durable – it’s what clear soda bottles are typically made from. PETE can be identified by the recycling symbol with the number 1 on the bottom of containers in the US. And they can be recycled – if your municipality bothers to do that…

Don’s water or soda bottles are another good option, and might allow a little more depth, depending on bottle. And even tomato or coffee cans could work, though not without some potential hazards, and perhaps larger than your flats would allow…

Best size for a pot depends on how long you intend to keep them in the pot… What is your normal process?

Thanks-I had not even thought of a couple of those. Ramen containers would definitely work, and I do have one kid still in college, living in a team house-they must go through lots of those. I am currently (had to get something as a stopgap) using the poly lined paper cup that does not need to be sleeved-something about the poly insulates it. But the bottoms do look like they would not last the whole season-they may end up being sleeved. The soda cans sound great, but a little time consuming, and we don’t drink soda. Takes forever to collect those, and there is a little competition with the ‘homeless crowd’. I would be concerned about stacking and storing those for reuse-after all that work, it seems like they would need to go 3-5 yrs. to make the effort worth ones’ while. I will definitely try out a few of the plastic ones-the cost for them new is quite low. I do keep most of the seedlings in the starter pots until Aug., or Sept.

Hi Jackie,

I have used several different sizes of plastic pots that you can purchase from McConkey here in So Cal. They are a bit more expensive than styrofoam, but last for many years (they also stack nicely for storing). I have tried the smaller “rose pots”, but have found that the 5 inch square pots work best for me. These go 9 to a “California Flat”. They allow good growth, while still being relatively more compact, and don’t dry out near as fast as the smaller pots. Over the years, I have lost hundreds of cuttings that were growing in the smaller pots in our heat.

David, the American version of the British “Steptoe & Son” was “Sanford & Son”, if that helps. The set was almost identical, but different actors were used. It was apparently pretty successful throughout the Western world, because I remember a Norwegian version as well. Was there a Dutch version? I will have to ask Michel. Whatever nationality, they would certainly be in favor of collecting free discarded beer or coffee cups to be used for other purposes!

Yours,

Betsy.

Yes, there was a Dutch version of “Steptoe & Son”–“Stiefbeen en Zoon”. This information courtesy of my co-editor… Not that it has any relevance to Jackie’s original question!

B.

without to have a beer out of the cups:

to save space at the flower window, I use the 0.2 l PE cups until the seedlings are placed in the greenhouse.~ May-June they will be repotted into 1 l rose containers.

cheers

Bernhard

Bernhard,

Such a treat to see all the young, healthy, new rose seedlings on what is a cold winter day in New York. They look so healthy and full of promise. Thanks for posting.

Jim P

We have a chain called Smart & Final locally where I can buy 16 oz. foam cups for a reasonable price. I’ve used them to pot up the wrapped cuttings I’ve been using and they’re on their second year. I save the four inch round pots from perennials I use in clients’ gardens and the circular pot flats when I can obtain them to plant both the cuttings and seedlings in. From the four inch rounds, I upsize them to either one or two gallons depending upon the individual vigor of the seedlings. Those four inch round pots have lasted years and seem the appropriate size for most of them until they outgrow them. At least they don’t fry as quickly as the traditional square “quart” pots we usually find “four inch” bedding plants in around these parts.

There are a lot of Smart & Finals around here. Will check, because the styro, even though not environmentally friendly, can be used over for about 4-5 yrs. That’s recycling in itself. The beer cups are the cheapest, but Costco carries the 10 oz., which is small. The styro really insulates the root from the heat which I find most valuable. I also have collected many, many 4-5" round perennial pots (from client installations-also where I got the carrier/spacers) to pot up in-also like the square gal pots-very space efficient. I would rather spend money on the fertilizers, etc., rather than on new pots. Eventually I will probably get ‘real’ pots.

Betsy and David–now that you say Sanford and Sons, it rings a bell. I don’t own a TV set myself, but hopefully my yd doesn’t quite look that ‘used’. But the spare room has 6 barrels for sorting recycling-and the door is kept closed, and all cans, bottles, etc., get at least rinsed before going in there.

If you live near a tennis club, they have an abundance of tall cylindrical containers that last 5 yr or more. But maybe too large at the base for your trays. I used them years ago for small trees from seed. PETE, and some are tinted too. About like the 20 oz pop bottles but straight sides make it easy to get things out again, and no cutting off the tops.

Why not just order cases of forestry bands from one of many greenhouse supply companies? They last many years (minimum of five years, possibly as much as 8 or 10, in my experience) and are ideal for seedling roses. The fact that they give you uniformity, maximize the usage of bench space (no gaps between containers) and fit in a standard nursery flat in a 6 X 6 unit grid makes them ideal for what I do. Buying by the case is very reasonable, price-wise. A case of 200 costs me $27, plus shipping. Considering how many years of service these are likely to give you, its a very inexpensive option, IMO.

Anderson Dies & Manufacturing makes 95% of the bands we typically see in the rose trade:

Anderson 3 and 1/8" X 6" band pots