Indian Paint brush and Gentiana Germination

Indian Paint brush and Gentiana Germination (post #16111)

kylefletcherbaker on Thu, 01/14/2010 - 08:16

Plant Propagation

Over the last three years I've tried in vain to germinate Castilleja coccinea? and Gentiana asclepiadeae seed with little to no luck.

The castilleja I was originally told was a semi-parasitic plant and to sow seed in and around established grasses. No luck. I was also told it could be sown singly and would germinate fine. No luck.

The gentiana has been treated with cool over winter fridge keeping, cold-warm-cold-warm cycle...nothing...ideas?

Here is what Jellito Seeds (post #16111, reply #1 of 3)

by SteveA in reply to kylefletcherbaker [original] on Fri, 01/15/2010 - 07:40

Here is what Jellito Seeds has to say. I think you are doing stuff not many other people have tried, so report back to us with how things go.

Germination: The sowing must be kept warm (about +18 to 22°C) [about 64 to 72°F] and moist for the first 2-4 weeks. After this period the sowing must be kept at a cold temperature (between -4 and +4°C) [between 25 and 39°F] for another 4-6 weeks. It is not so important if the temperature is higher or lower during the cooling period, but the cooling period has to be prolonged because the synthesis of the germination inducer, hormonlike acid, slows down or comes to a standstill. It is beneficial to cover the sowing with snow during the cooling-period. The temperature below it usually keeps in the optimum range of -4 to 0°C [25 to 32°F]. The sowing is kept moist, and the melting snow helps to destroy the shell, which is advantageous for the germinating seedling. After this cooling-period the sowing may not be immediately exposed to high temperatures. The most effective temperatures are between +5 to 12°C [41 to 54°F], even if germination has started. The best location for this sowing, even in March, April and May, is the open field, the cold frame or a cold greenhouse.

Scheduling:
Best Sowing Date: November - March
Sowing to Germination: 8 - 10 weeks
Germination to Transplant: 4 - 8 weeks
Transplanting to salable Plant: 6 - 10 weeks
Cutting-Back at Transplanting: Not necessary

Growing On:
Container Size(s): 1 plug per 8/9 cm (3 1/2''); 1-2 plugs per 11/12 cm (4 1/2'')
Vernalization: There is no current research on vernalization but a prudent recommendation for any perennial would be 6-12 weeks (a few might need 15 weeks!) at an average daily temperature of 40°F (5°C). Exposure to cold may not be necessary for flowering but might improve quality.
Forcing: This species is not a suitable candidate for forcing.
Fertilization: Medium (150-200 ppm)

--Steve Aitken, Editor, Fine Gardening

I knew that sounded (post #16111, reply #2 of 3)

by kmrsy in reply to kylefletcherbaker [original] on Tue, 01/19/2010 - 20:03

I knew that sounded familiar...this from High Country Gardens:
"Description: Castilleja integra

8-12” x 6” wide (seed propagated). Native to the prairies of eastern NM and Co, this Indian Paint Brush grows well throughout the high plains and intermountain region. Castilleja is a genus of parasitic plants that must tap into the roots of other plants for their nutrients. We send it with a pot of Fringed Sage as the host plant."

I realize it's not the same species of Castilleja, but perhaps the Fringed Sage would be more helpful than the grasses you're using.

Also (again, different species, but possibly helpful) Tom Clothiers archive lists this:
Castilleja miniata , Sow at 18-22ºC (64-71ºF) for 2-4 wks, move to -4 to +4ºC (24-39ºF) for 4-6 wks, move to 5-12ºC (41-53ºF) for germination.

Lastly, from the seed starting bible of Norman Deno:
Castilleja ;
"There have been suggestions that Castilleja seed is difficult to germinate and that chemical exudate from the roots of host species are needed to induce germination. None of this is in accord with [his results] and patterns were found that gave excellent germination without the addition of any exogenous chemical. Most of the species germ at 40°. The seedlings grow vigorously until the stem has elongated to the point of producing 5-10 true leaves. Then the seedlings lose vigor and die off showing the need for a host plant... Although germ occurs without any exudate from a host, it is still possible that a host is required for development of the Haustoria."

He goes on to list the germination steps for several species of Castilleja, but not C. coccinea. Unfortunately, I only have the first volume of his work. Later volumes might contain that species.

Hope something here helps.

_^..^_ Kitty, neIN, Z5

Gentiana propogation (post #16111, reply #3 of 3)

by Dmil07 in reply to kylefletcherbaker [original] on Thu, 09/30/2010 - 08:25

For the last few years I have been trying different methods of seed propogation and have had the most success with gentiana as follows:

wash for 3 days with 1000 ppm Gibberellic acid, change solution each day.

Using Deno's method, place seed on damp filter paper and check each week for 6 weeks.(transferring germinated seed is difficult.. (I use a tiny artests brush.) Transter to flats at app. 65 deg.

If no development in 6 weeks move to 40 deg.wash with H2O first as to much GA3 hastens germination but survival is doubtfull.. 40 deg.for 6 to 12 weeks then transfer to flats.

I have now managed to get 5 species growing in the garden and will try additional species next spring.

Indian Paint brush and Gentiana Germination