I haven't used styro cups for this...if I do they go into gal. jugs. When I use plastic covers I use stuff like sour cream, butter, cottage cheese, Yogurt, ect. containers and cut the center out of the lids and use the rim to hold the plastic tight.

Vera

Greengardener, I put my tomato seeds in individual styrofoam cups, but since the rubberband idea didn't work too well last year, I took quart sized freezer bags, snipped off the bottom corners, and placed them upsidedown over the cups, with the zippers left undone. So far, it seems to be working fine.

Bonnie

I put cellophane over plastic solo cups, most of the rubberbands did break, but I have my cups packed in tight enough into little carry flats that the cellophane just stays put anyhow.

I just sowed a bunch more veggies (peppers & herbs) in solo cups and I didn't even bother tying or rubber banding, just smoothed the cellophane over and its been fine in high wind and hard rain so far.

Here is what I've been doing for 5 years and has worked like a charm every year.

STYROFOAM CUPS

use finger to punch hole in bottom of cup. fill with soil half full for tomato seeds. Get soil good and wet. plant one seed and sprinkle with a little soil on top of the seed.

cover with store brand sandwich size ziploc bag with air holes in it.

I put the cups in an old carrying tray from the days when I bought my plants and the nursery. last year started using the wooden trays that clementines come in as well.

A trick I like with the tomato seedlings that is really good is filling the cup only half full. then as the seedling grows I add more soil to the top of the container to cover some of the stem. roots grow from where the soil was added and gives it an extra boost of roots.
The other thing that I do, if the seedlings are getting too tall before I can get them all planted, (happens every year), is I take the tomato seedling out of the cup, add a little more soil to the bottom, then put the seedling back in the cup again. Gives it just a bit extra soil on the bottom for roots too.

small containers like margarine, cottage cheese etc.

I just slip them inside a store brand ziploc bag with slits in the bottom and top of of the bags and zip them shut.

Instead of cutting out the center of the container to use to hold plastic wrap down, I cut up the container and use them to label my seed containers. I use a black paint pen to write with.

USING PLASTIC WRAP

I use the Glad Brand Press and Seal. it's still clear enough to get light through but not as clear as regular plastic wrap and is sturdier too.

I use this to cover 9x13 aluminum pans, smaller aluminum pans, cake covers etc.
I use this from April on and it won't hold up to NE winters and heavy snow cover and sleet and freezing rain.

I seal the press and seal to the edges of the container, then make slits for air holes with a small razor knife and then the trick to keep the press and seal on is to use cheap spring type wooden clothes pins.

I have found tons and tons of the wooden clothes pins in the dollar store. Just picked up more of them last week in packages of 72 clothes pins for $1.

Hope this helps

Fran

I use 1/2 gallon water containers, the bottom part, and the giant rubber bands. [They come 12 in a pack, differently colored, in the stationery store.]
They last pretty well. I've had a couple break, but so far the rest are holding.
The best I've found for the size container I like to use, are the bags that grape bunches come in! They already have holes in them, and they fit just right. And easy to raise if need be as the seedlings grow. No fastener needed.

so start eating grapes! Plus they're good for ya.

ellen

If I want to use cups and plastic wrap and keep it tight - I don't very often - I just pull it tight and sit one cup inside another of the same size. I have done the same with sandwich bags.

My gripe with cups is they tip over if I want to move several. I keep thinking I will put a large pebble or small stone in the bottom but I forget until I knock some over.

I used the plastic wrap at first but switched to some heavier plastic I found unused around the house. I found an old window winterizer kit and cut up that into sizeable pieces. I've also found that produce bags at the grocery store pretty heavy.

If i'm using sour cream containers, I just cut the center out of the lid and put the lid over top the plastic and use the lid to hold it in place.

For old plant containers (those white and black plastic pots you get at the nursery), I just use duck tape or masking tape to hold it in place. I let some over lap the edge and then tape it. Duck tape is harder to remove but it holds. LOL

Darn! Ellen had my "Idea of 2008" with the grape bags. They have gigantic holes in them, but they work great, even in torrential downpours. Be sure the drainage out the cup bottom is sufficient. (I always add that because we get a lot of rain in sprig here.)

Lime

"switched to some heavier plastic"
yes, I should have said, the plastic I use when I run out of grape bags is also the plastic that is sold to keep drafts from your windows. The other kind I found too light-weight.

er