Seeds that are surface sowed that require darkness for germ

Salpiglossis, Pansies, Gazina,: PKG says to press seed into soil and cover flat for total darkness. Why can't I just sow them 1/4" deep? I'm worried that they will germinate and I won't catch it on time and get them under lights just as they have germinated. I'm planning to be out-of-town for a few days and it is possible that they would germinate while I'm gone. Should I add 1/4" of soil? The seeds did plump up, sowed them on Saturday.

Hi:
If I'm not mistaken those are small seeds. In general, seeds are sown in depth 1/3 of their size deep. Small seeds that need darkness can't be sown too deep because they wouldn't make it up to the soil line before their internal food source and strenght wore out and they may rot before emerging.

For these seeds, I place a ruler on the soil sharp edge down, then gently wiggle it back and forth to create a furrow. Sow your seeds, then push the sides of the furrow together. That way the seeds will not be too deep.

I wouldn't worry about being gone for a few days. Just make sure the seed container is covered with plastic to prevent drying out, and out of direct sun. If they germinate before you return they may be a bit leggy. However, under lights, they will outgrow that and grow normal..

I have sown seeds for 40 years. I rarely buy plants if I can obtain the seeds from a reliable source. During the last few years, I sow seeds in my simple coldframe.

Pictured is a flat of common Geraniums, Dianthus, and Crownvetch.

I've missed checking them for a day or so and had the little sprouts pressed against the plastic wrap but I just take off the wrap, put them under the lights and they do fine. :)

Beautiful seedlings blomma.

Thanks for the advice. Nice seedlings. When did you start them?

I picked up the book The New Seed-Starters Handbook by Nancy Bubel. The book recommends 1/4" of fine soil cover. In past years I have tried salpiglossus from seed and tried covering the flat and bottom heat. Most didn't germinate and I dumped the tray in the flower bed, which is when & where they germinated. I'm going to add some soil and see what happens.

I think I started them in February since common Geraniums are included. I owned and operated a commercial greenhouse during the 80's and these plants were sown to sell.

Here is an excellent link to seed germination. Copy and paste it into your browser.

http://tomclothier.hort.net/

You proved my point when you stated that the seeds germinated where you throw them. No cover on them.

The photo is of my simple coldframe before I planted in it. That is where I sow seeds now. I sowed perennials in it in Oct. 2008 to germinate this spring. The seeds sowed in there are those that require coldness to germinate this spring. I have chicken wire across to keep out animals.

Thanks blomma for all the great information. I ordered a pack of Bullseye Geraniums, but my seed order has not arrived yet. Hopefully soon though since there a few things that I thought should be started now.

The gazanias that I sowed on Feb 8th are up....yeah. I have panies & salpiglossis in the same tray.

Joannabanana:

When you sow seeds keep notes on when you sowed them and when they germinated in days. That way you have a guide for next time. Mixing different types of seeds in the same tray can make it difficult to transplant those already up and growing, without disturbing those that haven't germinated yet. I always kept notes, then sowed the varieties in the same tray that had approximately the same germination days. A guide is the size of the seeds. Small seeds tend to take longer to germinate and start as tiny seedlings. Larger seeds are the opposite. I combined the same size seeds in the same tray as long as their germination days were within 10 days of each other.

I sow most in my coldframe now, though I have 4 trays ready to go because I ran out of room in my coldframe. The trays are drying a bit before I sow the seeds. After, I will place them by the window in my garage where they will get different temperature that they need. I have a plastic dome that I place over the trays to prevent drying out.

I don't mix seeds in the same tray anymore. Instead, I allow more room for each seed and I never use all the seeds at once.

joannabanana: Here is even a better link for seed germination I came across

http://grow.ars-informatica.ca/plant_index.php