D. filiformis: germination techniques

[jofarnen]

Hello all,


I have been struggling with Drosera filiformis from seed. The good news is I have a few "adult" plants on hand, but I really wanted to try growing from seed. 


I keep losing them to mold! I have tried a number of techniques, from aseptic/laminar flow hood propagation in various concentrations of MS, medium to quite a few combinations of sphagnum, peat and the other usual suspects. Even autoclaving media and containers, and extra attention to prevent contamination has failed.

I even went as far as to try a number of sterilization methods on the seeds themselves, but still end up with as of yet unidentified white mold that either wipes out the plantlets or consumes the seed before germination.


Oddly, I have only had this issue with the filiformis, other species of sundew planted at the same time using the same techniques do (and are doing) extremely well.


I am stumped.

Any suggestions?

[jdallas]

Hi Jofarnen,

If you live in a temperate climate such as North America or Northern Europe, just sprinkle the seeds on peat or sphagnum then leave the pots out for the winter. Shelter some from heavy rain, but freezing is no problem. When it warms in the spring you should have more of the little devils than you know what to do with. I find larger containers work best for this, that way seeds don't get washed away. D. filiformis being a temperate sundew needs that cold, wet period of stratification to germinate. When you do the stratification naturally, you have less issue with mold.

If you're trying to stratify in the fridge, you need to use copious amounts of fungicide even if you sterilize the media. I prefer sulfur based fungicides for this purpose since it lasts quite awhile.

In our nursery D. filiformis is so prolific among our outdoor plants, they are a bonafide weed.

Jeff

[jofarnen]

Thanks for the tips, Jeff!

I'll give the outdoor method a try here, but I fear out -20C winters at 10% humidity with constant winds might "freeze dry" them. I do have a large bog filter for my pond complex, I'll dump some in there too just for giggles. I have had difficulties in the past, particularly with temperate ferns and liverworts, even with mulching and the like. We either get bitter, dry windy cold with no snow, or so much snow I question why I ever left San Diego for Nebraska...

I have a few fungicides here at the house and access to far more at the university lab, so I'll give them all a try. (I had a windfall of seeds thanks to a family member's greenhouse being over run with them!) Do you think applying them as a solution to the peat or a spray/dropper type of application would be best?

[jdallas]

A spray application works well. With both seeds and cuttings I like to spray the media first, apply the seeds or cuttings, then give a light top spray before covering. Here's an example of the product I use: www.amazon.com/dp/B000M2VF14/ref=asc_df_B000M2VF143313978?smid=ATVPDKIKX0DER&tag=pg-1160-86-20&linkCode=df0&creative=395097&creativeASIN=B000M2VF14

To deal with the cold, dry conditions of Nebraska, mulch with a course mulch for the winter. Pine straw would work well. Remove it in the spring when the weather warms. If you sowed lots of seeds, you would probably loose some to wind, washing away, but you'll still have lots that make it.

Jeff

[jofarnen]

Thanks again Jeff!

I was at the hardware store the other day buying up egg crate in preparation for a bit of work with Darlingtonia, and they happened to have the exact item you suggested on sale, so I picked a few up (4 bucks a pop!).

While my current batch of indoor seeds failed, I had a nice mold culture going as a result, so I let them have it. Knocked the stuff down in 48 hours. A cursory examination under the microscope showed the mycelia were finished too.

Thanks for the tips! I can barely wait for spring now.

Have a neighbor a few houses down who was more than happy to have my son grab a few wheelbarrows full of humus/needles from under his white pines.

As for the indoor cultures, it is just the waiting game now. I've got some in the fridge and few few in the freezer, just out of sheer curiosity. (It's Ginkgo biloba season here right now too, so I may have to buy another freezer before deer season, but that is another tale...)