Here is my short list.

petunias,
snapdragons
tomatoes
peppers
herbs
lobelia
shooting star,(thymophillia)I think that's how you spell it
all from seed, I save tonnes of money, plants get more expensive every year around here

I also have cuttings from sweet potato vine and osteosperum

these I do every year but there is always more.

I grow things that I'm not sure I'll be able to get locally, or won't find the variety I want. I always grow annual phlox, asters, salvia and nasturtiums because they're pretty easy. Every year I start a few perennials indoors that I didn't already have. That is definitely worth the effort because perennials are usually $4-10 each to buy depending on the type and pot size. I wish I could start lobelia from seed. I have tried several times but the seedlings are so tiny I can't keep them alive. :(

I start petunias and impatiens inside, as well as ornamental grasses lately, and tomatoes and peppers. I've also tried lobelia and had a bit of luck with it, but it's tough to keep it going. Last year all my seedlings (everything) stayed really tiny for a long time and didn't grow that well until i took them outside in May or June. I'm not sure why that is.

Petunias especially the waves and large flowered superbissimas are worth starting under lights. Lobelia I can usually find cheap---however, if I start seeds
lobelia is better started in a south window. It is a part shade plant.
Tomatoes, peppers and sun loving plants do well under lights.

I start bedding plants under lights too, and the great benefit that I don't think anyone has mentioned yet is that you get to start gardening in late February or March, instead of May! Some things are suited for lights (peppers, tomatoes, onions, etc.) and some aren't -- melons, cukes, pumpkins all grow tall and spindly from the word go and then are destroyed by wind soon after moving them outdoors. This year I'll be starting onions (soon), hot peppers, tomatoes. I like that I can start varieties that local garden centres just don't carry.

Good point Don =:)

Since petunias were mentioned numerous times, I think I'll give them a try. DH chuckled over my tiny little leeks last year, so I think I'll start them sooner this time around. I obviously don't need to plant 30 or so tomato plants. I didn't realize I'd get such good germination! I absolutely love impatiens, so I'll have to order seeds for those, too. Hmmm. I may need to negotiate the installation of a few more light fixtures. I hope nobody wonders about the increased glow coming from the basement window, LOL !

Don, as a side note, do you grow everyday regular green peppers? I've had a heck of a time with them the last two years. I had what looked like blossom end rot on them two years ago (do they get that?)and last year something ate massive holes in them! At first I thought it was slugs, but I really didn't find evidence of slugs, and nothing else was eaten. Any ideas?

Thanks for the info everyone. Now, where's my seeds from last year and where's my new catalogues?

I always start tomatoes, peppers, herbs, eggplant and wave petunias from seed under lights indoors. A bunch of other stuff too, but these are the staples.

I can grow a very large volume of wave petunias from seed, whereas it would cost me a fortune just to buy a couple of these plants. I grow these from seed I collected from wave petunia plants. Even though they are hybrids, my wave petunia seeds always grow true to colour and I get tonnes of seed to keep planting.

This year I'm going to get back to starting a few perennials from seed as well, but I will be winter sowing those in milk jugs.

I always grow way more than I need personally, as I do stock gardens for my retired neighbours. Used to grow for my mom's garden as well, but now that she's passed and I no longer have to do that, I'm still trying to figure out the right volume of plants to grow.

I'm happier with extra plants because I always manage to kill off a few too many early in the planting season. I like the backups. When I know I don't need them anymore, and my neighbours get sick of my plants, I start giving them away to strangers :)

Strangers would love you !

I bought a seed saving book from Seeds of Diversity last year, but it's still on my large pile of reading to get to. I must put that further up on my priority list, as it seems many people here do it, and say it's easy to do.

I did some winter sowing last year with about a 50% success rate. Not bad for my first try. Since we have very little snow this year, if I get to it, my attempt will be much different than burying it in a 3 foot snow bank like last year =:) I digress.

Don, as a side note, do you grow everyday regular green peppers? I've had a heck of a time with them the last two years. I had what looked like blossom end rot on them two years ago (do they get that?)and last year something ate massive holes in them! At first I thought it was slugs, but I really didn't find evidence of slugs, and nothing else was eaten. Any ideas?
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I'm at a loss as to what ails your peppers. However I should perhaps mention that I have always pretty much failed at growing bell peppers, but have had much better luck with things like Hungarian Hot Wax peppers.

note on the blossom end rot, last year for my tomatoes in the greenhouse and the peppers in pots I mixed in a huge amount of blood and bone meal that I had laying around. I have no idea how old it was, it was sitting on a shelf in the shed and kept getting knocked over. I didn't have one tomato or pepper with end rot and that is a first for me. Cheryl

My season is so short here I dont directly sow annual flowers in the flowerbeds.Some of my favorites and very dependable are
petunias
dahlias
geraniums
dianthus annual and perennial
chrysanthemums annual ones
calendulas
osteospermums
marigolds.
I also start tomatoes and bell peppers every year
I sow so many things it really is hard to pick favorites
Jean

Just wanted to note on my list, nasturtiums are one of the items that should be in Don's category of do not start under lights. I really just sprout them inside and put them almost straight out. Not sure why but the few days inside seem to make them grow bigger in the long run.