capillary mat and damping off

I am trying to avoid losing everything to damping off again this year. So far I've done everything I think I'm supposed to do. I germinated petunia seeds in a dome on a heating mat. As soon as the sprouts appeared, I moved the seedlings under lights (2-3 inches) set on a timer for 16 hours, with a fan circulating the air. Even though I sterilized everything with clorox mixed in the water first, I'm still getting damping off. I just lost about 200 petunia seedlings. I'm wondering if it could be the capillary mat. The pots seem awfully wet. Could I possibly have put the mat in upside down?. The instructions that came with the mat said to put it smooth side up. I thought that's what I did, but actually both sides seem smooth. Could some one please tell me if I should have the DARK side up or the WHITE side up? Currently I have the WHITE side up. I threw everything in the trash because I know it is all ruined, but I'd like to try again. Any help would be greatly appreciated.
Lin

I am so new to this I hate to give advice. You really need to hear from some of the experts, BUT from what I understand you can help prevent damping off by spraying the seedling mix with a weak solution of Chamomile tea. It is a natural fungicide. The neighbor who helped me get started had me spray the seedling mix with something called Benamyl( I think that's how you spell it). It is a powder that you mix with water. She said it only needed to be done once. You can get it at a GOOD gardening store--perhaps not one that just has a gardening section. I also saw something on one of the gardening websites that was advertised to prevent damping off but I don't remember what it was. Look at Gardener's Supply Company and Lee Valley Tools--maybe even the seed suppliers under seed starting equipment. I also know they can't be kept too wet. Some of my seed are just barely up so I'm not to the damping off stage. Good luck. This must be discouraging.

I hope you'll hear from somebody who knows which way is up, so to speak. Meanwhile, take out the capillary mat! If you think your seedlings are too wet, they probably are, and that will definitely cause problems.

When seedlings are young with few roots, you may not need to water them for several days at a time. When the medium seems dry (touch it), it's time to water again. I water from the bottom by pouring 1/4 inch or so (more for larger seedlings) of water into the flats holding my 6-cell packs.

Good luck!

Can you call the manufacturer of the mat and ask them some questions? Who made it?

To avoid damping off almost completely (say effective in 99% of cases), replace your normal compost in the top 1 - 2 cm of the pot/tray with moist vermiculite and sow the seeds in that. Damping off is a fungus disease, the spores of which are found in, particularly, peat-based compost, and which attacks the shoot between the seed and the cotyledons (seed leaves). Since vermiculite is inert and sterile, no spores are found in it.

The root will quickly find its way to the nutritious compost below the vermiculite, and you will get plants not shrivelled up corpses.

I lost about 95% of my seedlings to this disease until I changed to the above technique. (Healthy types will want to make sure that the vermiculite is damp when handling it as the dust is potentially hazardous, but, unless you are using it in industrial volume, I think you will be OK.) Don't know what the situation is in the US, but over here, the garden centres go into rip-off mode when selling small quantities of vermiculite. They charge ~ £3-£4 (~$7) for 5 litres. Hence I buy 100 litre bags from a horticultural wholesaler for £10 - saving myself £70!

Vermiculite is also good for 'cutting' normal compost into seed compost. I make my compost from peat, grit and 'home-grown' vermicompost. But this is too nutritious for seeds, so I mix it 50/50 with vermiculite, with good results.

Good luck.

Mike

I would not use the capillary mat. Keeping the seed mixture too wet is number one reason for damping off.

Just my 2 cents, but I use water mixed with hydrogen peroxide (3 %) to water my seeds & seedlings. A ratio of 1part H2O2 to 19 parts H20. Last year was my first year starting seeds & I didn't have any damping off with 3000 seedlings. Of course as soon as I put them out the rabbits ate tons of them. But, that's another problem. There is some interesting info on Dave's about hydrogen peroxide. Do a search on it in the forums for more info. It seems to have some other uses that I would like to try.

So far I have over 1500 babies this year & no damping off. I don't know where I read about it, but it seems to work for me.

Last year I used a soilless mix of 1/3 peat, perlite, & vermiculite. This year I started with that but I got tired of sifting the peat so now I am using straight vermiculite. I also, get large bags of vermiculite at our city co-op (farmer's supply store).

Hope that is some help and encouragement.

You will still need to make sure they are not too wet as mentioned by others.

Pam

This message was edited Mar 16, 2005 2:38 PM

I have a capillary mat but have never used it with small seedlings, only after I have transplanted them in pots. Mine is green on one side & white on the other. I use it with the green side facing up. Have never had a problem. Could your seedlings have been too wet right at the beginning when you put them on the capillary mat? I have read that the vermiculite method that cinemike is talking about is supposed to work well. Also the peroxide & chamomile tea. There is also No-Damp which I have tried & it works. Since I switched to Jiffy 7 peat pellets I have never lost any seedlings to damping off. There are a lot of people that do not like jiffy 7's though. I have been using them for about 15 yr. I wish you luck.

I used the i to 20 mix of Peroxide to water to water my seedlings this year, watering from the bottom, and have had no damping off. I use the strip trays for seed starting and also Jiffy 7 peat pellets for larger seeds. The strip tray sits ona kind of capillary mat, but doesn;t have different colors top or bottom. inside another waterproof tray. It is so easy to lift out a few seedlings without injuring roots with the strip trays. here is a photo of one with some of the seedlings already transplanted. DonnaS

Those seedlings sure do look healthy Donna.

I wouldn't use a capillary mat for starting seeds, just later for seedlings if you must. I usually use capillary mats only for small pots,when I'm unable to water on a regular basis.

Petunias can be touchy--they like to germinate at about 80F soil temperature (that means around 85F air). You should always thoroughly soak the starting medium 12-24 hours ahead of time, and use a good no-damp product--either commercial or, my favourite, H2O2. (Hyrdogen Peroxide). If you firm the dampened soil, press the seeds into it, and then cover lightly with a piece of plastic you won't need to water for several days. ALWAYS bottom water with tepid water. Lift the plastic at least once a day--turn it over because there will be condensation. After good germination the petunias can grow at a much cooler temperature but continue to bottom water.

Good luck--it's really frustrating to lose seedlings, isn't it!