Photo by Campbell & Lynn Loughmiller, courtesy of the Ladybird Johnson Wildflower Center
Growing Method for Seeds
Species: Eustoma Exaltatum, Texas Bluebells
Author: David Burkel
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"What worked for the seeds that I was able to get to maturity. I don't have enough experience to know what doesn't work yet so I can't say how much of this is necessary.
- The seed was about six months old. Source of seeds: collection from Johnson County.
- The seeds are really tiny. Note: stick shown in photo is a toothpick. Seeds are tiny dark brown specs.
- I don't know how important it was, but the soil mix had 10-20% black/gray clay soil I got from the yard which is the typical soil base on which this species is found growing in. I also added about 10% lava sand and 10% mushroom compost (cow manure would do the same) and the rest was homemade compost plus some expanded granite to get it to drain properly. I have a hunch that any kind of potting soil would probably work but can't say for sure as I haven't tried.
- The seeds were surface sown early February in 2” square plastic pots sitting in solid bottom 24 x 48 nursery trays with humidity domes covering them and with the openings in the dome almost shut. They are picky about having consistent moisture before, during and following germination, a period of up to 6 weeks or more.
- I kept enough water in the bottom tray to keep the soil in the pots wet. Damping off didn't appear to be an issue even though the conditions enabled some interesting mosses to grow as well.
- The trays were kept by a window with the following type of grow lamp that was kept on continually: jump start grow light
- I also used a 10 x 20 heat mat and thermostat set at 80 degrees as it was February and a little chilly by the window but I don't know how necessary this was.
- I didn't notice any difference in germination rates for cold striated vs non-striated seed.
- Plants prefer full sun. They will grow and bloom in part sun, but the flower stalks will lean and lay down in the direction of the dominant sun.
- If you choose to direct sow into soil outdoors, choose a location that tends to collect water after rains, such as a low spot, a place where you might also find crawfish holes. Outdoor sowing seems likely to require you to keep the soil / seedbed moist, almost wet for an extended period.
The two inch pots made it easy to transplant to larger pots later, but limited the number of plants that could be grown per tray. In lieu of the individual pots, I would try a 12 x 24” tray with holes almost full of soil and transplant seedlings when they are dime to nickel size which was about 6-8 weeks."