Calochortus from seed - planting box and nursery pot questions

Giant Coreopsis
Tue, 22 Oct 2019 15:47:35 PDT
Hi George. 

I have tried plastic pots from the nursery and wooden boxes that I built, and my advice to you would be to try both and see what works better in your conditions. 

The main advantage of wooden boxes in my experience is that they breathe well and provide some insulation from the heat of the sun on the soil. One year I planted many thousands of seeds in wooden boxes and had massive germination rates. However… The wooden boxes were hospitable to pathogens and I lost 90% of those seedlings to damping off, which had never happened to me before. (I’m in LA, my seedlings are/were outside, and that winter wasn’t especially wet but it was foggy.)  

I more often but not exclusively now use 1 gallon or 6 inch plastic nursery pots. I have not had a damping off problem with them, but they do get hot in the sun, if that’s an issue for you, and they do retain more water,  Which becomes an issue here as the seedlings pull back in March or April. 

Over the summer, bulbs left in the wooden boxes have not rotted because the boxes stay dry, but bulbs left in the 1 gallon plastic pots have been less reliable. 

Given that my own experiences don’t drive neatly to one conclusion, I tend to use multiple methods simultaneously and see what works in a given year.

When in doubt I personally would take Kipp’s considered and methodical advice over mine lol


On Oct 22, 2019, at 11:54 AM, George Goldsmith <> wrote:


Another option for growing Calochortus seeds this fall is to use planting boxes, like those described by Hugh MacDonald in the "Hugh MacDonald's Calochortus Seed Planting Instructions" page.  The boxes are just under 6 in. deep.  Here my questions are:  How many years can the young bulbs stay in the boxes before they require deeper soil?  (I'm considering C. catalinae and C. weedii var. intermedius.)  I'd like to move them as little as possible.
Given that the new bulbs would stay in the box until they must be moved, how close together can the seeds be?  Hugh's comment was that "Seedlings tolerate ½ - 1 in, but will eventually need more space.  If I plan to keep the bulbs in the box as long as possible (given the 5.5 in. depth), how close should I start the seeds?

Another option is to use the standard 6 in. diameter x 7 in. deep black plastic nursery pots.  They have more depth than the boxes but less than a raised bed.  Could Calochortus be planted in these such that they could be left there until a flowering bulb develops?  If so, how many seeds could be planted in a 6 in. diameter pot?  Or is it better to plan to remove the small bulbs after a year or two into something much deeper?

If anyone has some tested start-to-finish scenarios for growing Calochortus, whether in raised beds, boxes, or nursery containers, highlighting was really worked and what failed, that would be helpful.  This is my first serious attempt at growing these wonderful plants, and I'd like to bring as much of the collective wisdom to bear as possible.

Thanks in advance for any replies.

George Goldsmith
USDA Hardiness Zone 10a; Sunset Climate Zone 19
Chamise Chaparral Plant Community

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