When growing small flower seeds use biodegradable egg trays. When the seedlings are ready for planting in the garden just pop the whole tray in the garden and cover tray with soil.
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When you buy your eggs, some of the containers, like Eggland's Best, are clear plastic containers. Buy those and save them for starting seeds. They have a clear plastic cover that covers where the eggs sit.
A way to 'make' peat pots is to cut up the 100% recycled newspaper egg cartons. Fill with soil and start your plants, transplant entire piece into ground, wetting the egg container just before placing in soil (this helps to quicken the decomposition process).
The cavities in egg crates are just the right size for starting many types of seeds. An added advantage to the paper style is that it can be cut apart and the seedling planted in the soil container and all.
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Paper egg cartons work wonders for starting your seedlings! Cut off the top of the carton and place under the egg compartments.