I’ve had great success with using Hydrogen Peroxide for the few cases of damping off that I’ve encountered. I just run a drop up and down the stem and then let the drop go into the soil.
Alicia, I use Miracle Gro potting mix for tranplanting well rooted cuttings, but would not consider it on new seedlings. I use Sunshine Mix #3, and agree with everyone that mentioned low fertilizer for young seedlings helps survival.
As for germination rates, I think that there is some debate about how ripe the hips should be. I have seen lower germination rates in green hips, but better germination rates in some varities that are showing some color, but not completely red/orange. I think that it is very varietal specific. I don’t think that seedlings from greener hips should have a poorer survival rate.
Jim Sproul
For me, I’ve had worse germination from early picked hips. My best germinations seem to be at the 130 day level, at least for this season. I know this is different than what most report, but that’s the way it is here for me.
Alicia and others:
These are definitely good questions. I need to learn more about what to do with germinated seeds, as I have lots of problems. Here is what I have learned from my work:
I asked the horticulture faculty member in my department about growing mixes after I had killed a hundred or so R. rugosa seedlings. He said that the cheapest mix component is peat moss, so it tends to dominate. As a result, most commercial mixes contain: 1) a wetting agent (typically a detergent-like chemical), because peat is hard to dampen once dry, 2) fertilizer, because peat is low in fertility, and can absorb nutrients as it breaks down, and 3) lime, because peat becomes acidic with time, and most commercially grown seed crops (annuals, vegetables, etc.) don’t like an acid mix.
My big problem was the lime, in combination with very lime-rich well water. I switched over to making my own mix: equal parts peat, vermiculite, and perlite. Even then, I need to use an acid fertilizer once the seedlings are growing to prevent chlorosis. Chlorosis in this case is yellow or white leaves, often with green veins. It is casued by an iron deficiency which is caused in turn by high pH (too much lime, for example). R. rugosa is unusually sensitive to iron chlorosis.
My survival rates after germination are low, often less than 50%. The worst are in diploid crosses where one patent is a rugosa, or North American species, and the other is a polyantha or similar. Really strong crosses, like pure rugosa and most species OP seed, show less than 10% losses (and higher germination).
The only trend I have seen with time is that the last seeds to germinate in any cross tend to grow poorly. If you wait to pot them up until they look strong, you probably don’t see this. They don’t make long roots, often are abnormally thick, and may have odd-looking cotyledons. They rarely survive for me.
I have a related question: If a cross is producing both recurrent and non-recurrent plants, do the recurrent ones tend to germinate early, or is there no relationship?
Panic… all 21 0f my seedlings are in miracle grow. They seem to be ok but there is some leaf burning. I do have sunshine mix as suggested by George Mander, but it was all the way out in the garage! Thanks for the info. Robyn Swesey
Since I switched to the ProMix I’ve not had any of the problems I had with the Miracle Gro. Boy do I feel stupid in retrospect, but at least I got it straightened out early in my germinating season so I have many, many healthy seedlings now. BTW, I also tried the soilless Ferti-Lome and it worked well, too. I like the ProMix better, though. It has a very mild fertilizer and it has water crystals which seem to help when I don’t get to watering quite as soon as I should.
Glad you found out about the MG in time to save your seedlings, Robyn! That leaf burn is not good.
Alicia