I know it's still really early in the year, but some plants recommend seeding 4 to 8 weeks before the growing season! By starting your own seeds instead of buying plants, you know that they've been grown organically and it cuts down on packaging. We started some of ours last weekend in an egg crate and some recycled pots. Here are some tips on starting your own.
Timing:
Know when to plant - timing is everything and to do so you must know the frost-free date in spring for your particular area. Here's an article from Organic Gardening to help you determine when to plant, and when to start your seeds.

Containers:
We use egg cartons and recycled pots from other growing seasons. There are also kits available, but those you have to buy new. Non-plantable yogurt containers, plastic lids and berry containers work just as well (but you can't plant it in the ground with the seed) - just make sure to punch holes in the bottom for proper drainage.
Potting Medium:
Some guides will recommend specialized mixtures of perlite, vermiculite and peat moss, topped with other types of covering mediums. We've had good luck with straight seed starting mix or even potting soil for something simple.

Keep it Warm and Moist:
Finally, keep your seeds well watered and someplace warm with a bit of light. Near a heater vent is a great place to start, or cover with recycled plastic wrap if your house is especially dry.
See Organic Gardening for more tips and a more detailed how-to.
While it doesn't sound very green, a growlight can really get your plants off to a healthy start. You can get LED and Fluorescent lights that don't pull very much energy at all, and for me, a light has made seed starting incredibly successful. IKEA has both cheap lights and timers, and I repurposed an old kitchen cart to hold everything.
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If you have a window with good southern exposure you could do without the light but it's still a good thing to have. The plants will grow more and be stronger for having the light. Be careful about plants being to cold (to close to a window) or to hot. I bought a small heat pad especially for seed growing and it works great. It has small power draw and can be used again and again. Delicate seeds should be watered from underneath. I use the recycled plants and place them in a large tub or deep lid.
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Coir is a greener alternative to peat moss.
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I am going to get started early this year, my only problem is that I don't an extra room to grow things in, so my cat knocks over the containers, like daily. Last year I put some in my bedroom, but it's mean keeping my cat out of there all the time. I might get a little mini indoor green house, unless anyone has suggestions?
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One way to keep your cat away is to booby-trap the area around the plants to make it unpleasant to walk on--they make sticky-tack paper and little mats with plastic-nub "spikes" to lay around plants (I've seen these at Daiso and other asian import stores). Amazon sells an electric shock mat, but it seems incredibly cruel to punish a cat for being curious. Also, having a container of wheat grass growing for the cat at the edge of the "keep off" area might also help curb the curiosity.
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Thanks for the tips Mylica!
view Melissa A.'s profile
LOL Melissa, my problem is that the cats eat the seedlings.
The egg carton thing hasn't worked for me - too small, dries out too fast. No matter, since I have old plastic pots, too... if you Google Making Pots from Newspaper, that's also an option, and since you can plant the pots, there's less transplant shock.
Winter sowing is a good practice if you want the earliest start without a grow light... gardenweb.com has a forum all about it.
OK, time to go home and see if my bunching onions are up.
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I used yogurt cups and punched holes in the bottom to start my seeds last year. I ran into the problem that some of my seedlings got very "leggy" and needed a lot of support when I transplanted them outside. For my pepper plants, I snapped a bamboo skewer in half and loosely tied a thread of yarn around them to keep them standing up. It worked wonders. The peppers were so happy that come fall when everything else died off, they were still green and lively. So I brought it inside and its been blooming all winter! I even have a little pepper growing at the moment.
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