Diatomaceous Earth as a seed starting medium

[b54red]

I am heading to Auto Zone today and see if they have it here. I have been having a terrible time with damping off due to the high humidity in my greenhouse. I haven't found a product that will maintain a dry surface to prevent damping off during times when our humidity levels are near 100% and that has been most days lately.

Ray does the surface stay dry enough to prevent damping off? Is dust a problem since I will be working with it in a greenhouse? Do you have to keep bottom water available all the time of do you just water them every few days that way?

Ray I am really excited about this. It may be the solution to my damping off problems. The last few bags of Jiffy and MG seed starting mediums I bought had mold inside the bags when I opened them. Quality control seems to be a big problem with most of the products I have tried with one bag being great and then the next one will be lacking in some way. I am also going to try coconut coir and may do a comparison.

Thanks for posting this information.

[RayR]

I haven't had any damping off problems with DE. I've seen a number of references about professional growers who use silicate minerals, mainly coarse sand or crushed granite (bird grit) as a top layer over a seed starting medium to prevent damping off. I've done this myself with great results, the only times I've had any damping off problems was when I was using seed starting mix alone. I've seen a recommendation from a hydroponics grower to use DE as a top layer over seed starting medium for the same reason. I don't know if the effectiveness is due to a dryer surface or if the mineral layer is just inhospitable to the growth of damping off pathogens, maybe both, I don't know for sure, but it seems to work well.

There is some fine dust even with the granular DE, but not bad and only when first pouring it out of the bag. Misting it good with water will eliminate any dust kick up when filling your cells.

I judge the bottom watering by the color of the top surface, when the DE is getting dry it appears very white, when it is moist it turns darker and the earth tones come out.

It'll be interesting to hear your results.

[b54red]

I'm going to give it a try if they have it at the local Auto Zone. Thanks again.

[meadowyck]

I'm still on board to do this but with the visit of family I've just not had time to start, will be though coming monday night after they fly home...LOL I love family but I also love the down time....LOL

[b54red]

I got the last bag at my local Auto Zone and they won't be getting any more for a week or so. I'll try it with some fall seeds and they are all small so I will get to see how it works on those tiny seed.

[rsrb]

Given all the interest in DE as a starter medium I thought I should report back. By the time I found my bag at a far away Autozone it was too late for summer, but I did try using it to start some fall plants. I put them outside, where it's warmer these days. (is this the humor column?) So far some of the seeds --both big and little ones--have been happy on my deck. "Homemade Pickles" cucumbers from Botanical Interests are the most vigorous growers. Broccoli (Calabrese) and cauliflower (Snowball x) are coming along nicely. However, the two squashes I tried (round zucchini and butternut) are so far not germinating. I know it would have been a stretch for the butternut to finish growing, but not impossible. Basil also not germinating but maybe the seeds were too old, or maybe they don't like DE. (squash seeds were vintage 2012, so they must have a different issue.)

[RayR]

rsrb, Give us some pictures when you get a chance.
How long have they been growing in the DE and what have you been feeding them?

[b54red]

So far the results are very good on the few seeds I have started in the stuff from Auto Zone. I planted some spinach on the 16th and had one pop up on the 18th and most are now up. That is far faster than I have ever had spinach sprout. My biggest worry with the spinach will be when it comes time to transplant them. I just don't know if few roots of spinach seedlings will cling well when trying to set them out. I will be starting some more fall seeds this week. I love working with the stuff. It soaks up water from the bottom much faster than any other medium I have ever used and the way it turns white when dry is an easy signal that they may need a bit of water. One thing I did learn is you want to do any leveling before you get the stuff wet. It is very easy to smooth out flat when dry but not when wet. I have really high hopes for this, so thanks again for posting the tip.

Bill

[meadowyck]

Well, my plans to have seeds started by now have been put off time and again, but finally TODAY, I will be planting, hurray..........

[b54red]

Well I have found one thing out about the Ultra-Sorb that I will have to watch out for and that is when it dries out it really dries out. When it starts turning white on top it is best to go ahead and water from the bottom right away and don't wait too long or your seedlings will wilt badly from getting too dry.

[RayR]

That's right. The technique is just passive hydroponics. Instead of using the color of the surface as a signal as when to bottom water, you can keep some water/nutrient solution in your tray at all times, the DE will draw up the liquid through capillary action as needed. There is always plenty of air space between the large DE particles so there is no worries about water logging like there is in seed starting mix or potting soil. It's kind of like a miniature SWC except you are using a totally inorganic medium to anchor the roots.

[Diriel]

I am going to be growing some Prue tom's and some Rooster Spur peppers this next year.

-- http://www.seedsavers.org/Details.as...o=1467%28OG%29 --

My question is... does anyone have a good idea about how "well" a Prue would do in a 5 gallon self watering bucket setup? Should I go with something like an 18 gallon self watering? I would kind of rather not go too much larger as the prices of the containers get drastically more expensive.

Thanks for any feedback!
Gary
P.S. I am still considering a 2nd Tom. Variety of some kind. I am in 9b in So. Cal. Near Bakersfield, so it gets pretty hot here. I want a variety that has a lot of flavor.

[RayR]

Gary, you should have posted your question in the "Growing In Containers" forum.
Aside from that, one Prue should do fine in a 5 gallon bucket.

[Diriel]

RayR,

Sorry sir, next time I will definitely post in containers forum. Thank you for the reply!

Gary

[lakelady]

So Ray, how did the tomatos fare during the summer having had those wonderful roots to start off? Did you notice any differences in growth and production?