you might want to try germinating indoors under lights , grow them for a week or 2 than move em to the greenhouse.

Only certain types of plants will germinate reliably at less than 60 deg. F. Most plants need to be between 65 and 75 deg. F to have the best chances of germinating. I have also found that the lower the temperature and the higher the humidity the better the chances that the germinating seedlings will damp off.

Last year, without extra heating, I was averaging 50-70% germination. About 80% of the trays had some damp off which required the use of a homemade sulfur-based fungicide.

This year, I am starting all trays with heat mats (with a thermostat to keep them at 72-75 deg. F). I am getting 80-100% germination and have had only three trays, so far, with damp off problems. I have one tray of Impatiens that had 100% germination, a new record.

All trays are started in the basement under lights. Here is a picture of the nursery. The heat mats are on top of a 3/4 inch layer of aluminum foil backed urethane foam.

{{gwi:288873}}

Once they germinate, I remove the domes as soon as possible and move them to another area to continue to grow under lights. When the plants get real leaves, I transplant to 2 1/4 inch cells. After about a week, they go out to the greenhouse which stays between 48 and 80 deg. F.

Steve, if you can even spare a dark, warm area in your house until seedlings begin to emerge you'll do OK. My germination room is without light most of the day except for the dull glow coming from my coal stoker. I slide the seeded, watered trays in 13 gal kitchen garbage bags and set them whereever there is a level area off the floor.

After a few days start peeking into bags twice a day with a flashlight and at signs of life then you can peel the bag off and move them to the greenhouse. Some flowers may germinate in as few as 2 days; others may take a few weeks. Some plants may still not like the cooler nights; others will grow better than inside, even if you have lights. And read the seed packets first... there a a few flowers and herbs that do need light for germination but they are the exception.

Thanks folks! (especially cottagefarmer for the pic).

Starting them indoors is a great idea (one we've done for years before the gh) BUT, at the moment we are living in 50% of the house space (about 700 sq ft - few to no basements in our part of CA) as the whole front half of the house is still torn apart from a remodel.

At the moment the gh is best "open space" to even put down a few trays so...I'm going to mix the ideas suggested here and start them in the gh under heat mats in covered trays AND boost the air temp a bit as well.

I'll let ya know the result in a few weeks.

Bmoser
Where did you ever get this statement "there a a few flowers and herbs that do need light for germination but they are the exception."

There is a big difference between "need" and "prefer"

We germination 400 verities each year 70 percent prefer light and are surface sown. 10 percent prefer dark. 20 percent don't care.

Some of the info in this thread is suspect.

The following info is from "The New Seed Starters Handbook" by Nancy Bubel, Rodale Press

Flower Seeds that Need Light to Germinate

Ageratum, Alyssum saxatile, Bellflowers,
Begonias, Balloonflower, English Daisies,
Browallia, Chinese Lanterns, Foxglove
Coleus, Chrysanthemums,
Godetia, Columbines,
Impatiens, Edelweiss,
Kochia, False Rock Cress,
Lobelia, Feverfew,
Mignonette, Gaillardia,
Petunias, Maltese Cross,
Portulaca, Oriental Poppies,
Scarlet Sage, Primroses (except Chinese),
Snapdragons, Rock Cress,
Strawflowers, Shasta Daisies,
Sweet Alysum, Sweet Rocket

I've also read on a number of gardening websites that these are the only seeds that need light:
Seeds That Need Light to Germinate

Ageratum
Astilbe
Balloon flower
Cleome
Coleus
Coreopsis
Impatiens
Mexican sunflower (aka tithonia)
Petunias
Shasta daisy
Snapdragon
Strawflower
Stock
Sweet alyssum
Yarrow

Not very many considering how many thousands of seed varieties there are available.

Are the pink lights worth it? They are alot more expensive.

(or is it just your camera?)

Anyone know of a seed that is surface sown and needs dark to germinate?

The reason the fluorescent lights in the photo appear pink is shown in the following diagram:

{{gwi:293699}}

In the interest of conserving energy, I am trying to minimize the waste by not generating any unnecessary light and by using fixtures with electronic ballasts which are approximately 83% efficient. Feeding 26 fixtures can make for a huge electric bill.

I have to agree with mylu. At least 70% of the seeds I started recommend light to germinate. Thanks tastefullyjullie for posting the lists and the reference to Nancy Bubel's book, which is a real bargain at $20 for those of us that are starting seeds.

I don't have the book, I just found an article online that referenced it. All my books are $7 or less :)

Actually, it's only $11. But that's the last I'll say on the subject because I really don't care. I was just trying to defend Bmoser because he's been a tremendous help to me in getting me greenhouse plants going.

Here is a link that might be useful: $11 book

So the lights are grolux? Do you know the plant available photons for grolux vs a standard tri-phosphor? Thanks cottagefarmer.

I've ben watching and trying to make my own call on this..

Being a cold zone 5 until recently, i've begun to move all my cool weather flats like lettuce out to the greenhouse to see how they can handle it..we do have a kerosene heater at night if we have to, but the price of even kerosene makes for some pretty pricey romaine if you know what i mean..

I have a big, sunny south window where i start all seed and then slowly move them out to the gh once they have a good two sets of leaves and look sturdy..The greehouse runs 40 at night and into the 70's during the day, but it is not as airtight as it could be..

So far, I have some pretty nice stuff out there for this time of year and i will be happy when i can get all 25 flats out of my kitchen and into the gh..

I think you have to try each type of seed and see how it adapts to your inside and gh temps..i think it is a real hit/miss situation..

ruth r\

Not sure about the triphosphor lamps. Triphosphor mixtures are used most commonly in the "compact fluorescent" lamps which don't have enough power output. The 80 Watts from a convention 48" fixture is barely enough for plants as it is, having to have them only a couple of inches away from the plant surface. Conventional fluorescents lack the big red peak, I think. They typically use just two phosphors, one big one in the green and one in the blue (the $1.50 "cool white" lamps).

Here is an article I found that did an extensive comparision, but for some bizarre reason, they converted all the graphical information into huge tables of numbers. More suitable to robots, I think.

Here is a link that might be useful: Lamp Comparision

Too many subjects in this post...What bothers me is sometimes folks make statements that aren't correct and others believe them. That's just me. Take what you read here and confirm and verify 1st.

Remember the word "require" is different then "prefer"

Every species of plant has different requirements for germination, temp, light, water ect. One question asked. Do surface sown seeds "require" dark. Answer, depends on the seed. Some do some don't. Same with every seed. There's tons of info out there to verify the requirements for what you are germination. A good tip is to start a database of your own and keep detailed records. Then modify what you did last year if your results were not up to par.

As for growing on temps. I read countless post of folk who's g/h's fluctuate way to much 20 degrees or more. When growing in a g/h try to maintain a steady temp. Large temp swings cause issues you have to deal with. Mainly internodal stretching. Our grow on temps are from 55 to 60 degrees for as long as we can maintain it. Now as the sun gets higher it's harder to do. Our heaters are set to 55 and our vents 60 and exhaust to 62.
Don't believe me, research it first. And no I didnÂt spend the night at a Holiday in Express.

Your question. Any seed we sow that is very small and requires dark is surface sown. It's one thing to sow 4000 seeds in an afternoon it's another to try to bury 4000 seeds like Astilbe..
I can get specifics later if you would like.
and it was Holiday INN not IN...