Jane, thanks for the suggestions. I can rework the mix. Can I pick your brain further: 1. Any commercial products you like that qualify as loam? That ingredient always stumps me and the native soil here ain't nowhere close to loam. 2. How do you feel about Perlite as an ingredient in this situation? Asking because I came into a big pile of it. 3. The sand I can most easily get is playground sand. I assume I need to rinse it in case it is full of salt? 4. Btw, I actually think the area's decomposed granite may also be a good primary ingredient for this purpose because it contains everything from fines to grit to irregular pea-sized bits and retains more moisture than I expected before I tested it. Chris On Aug 16, 2013, at 5:07 PM, Jane McGary <janemcgary@earthlink.net> wrote: > To address some of Chris's other concerns: > > Probably Mike's suspicion of excessive drying is a good one. The mix > Chris describes probably doesn't retain any moisture. Even though > Calochortus often grow on slopes and in rocky ground, the main bulbs > are deep in the soil and the plants are often surrounded by rocks, > shrubs, and grasses that help the soil retain some humidity. Rather > than adding a "water-retentive layer," I would suggest revising the > soil mix to exclude peat (which dries out and is very hard to > rehydrate) and bark (which I believe to be deleterious for most > bulbs), and instead incorporating some sand (as coarse as possible, > but with some fines) and loam or leafmold if it can be obtained. If > it's not possible to replace the existing soil, Chris should sprinkle > it lightly occasionally during summer -- just wave the hose at it. > Also, a gravel mulch will help both to retain moisture and to support > the stems. Although some Calochortus grow naturally in stiff clay > soils, such as adobe, I have not found this necessary for any of > them, or indeed for any California bulbs. > > Calochortus bulbs move downward very quickly, e.g. 4 inches in two > years. In many species new bulbils grow on the stems above the main > bulb, and these eventually grow to flowering size, especially when > the parent bulb gets eaten. You can hasten the process by detaching > the bulbils and planting them a little distance away. I don't know > how far the roots extend below the bulb as I have never lifted any > when they were in growth, but I don't think it's very far as I didn't > find them extending beyond the mesh baskets I grew some in. I > wouldn't expect them to grow more than about 10 inches (30 cm) below > the soil surface, though. > > I have at least two Calochortus species (C. palmeri and C. dunnii) of > which I have only a single clone, and they have produced fertile > seed, so I suspect many or most are self-fertile. > > All the Calochortus flowers are done here now, but I'm still waiting > and waiting for the last two (C. plummerae and C. weedii) to ripen their seed. > > Jane McGary > Portland, Oregon, USA > > > At 04:37 PM 8/16/2013, you wrote: >> Thanks Mike. I will test your drying-out theory this year. Everything you >> read about Calochortuses tells you to make sure the mix is well-draining, >> and I have only ever seen them in the wild growing in very well-draining >> situations, so I may well have overdone it. a) How deep >> Calochortus roots tend to extend below the bulb (esp for >> the various Mariposas)? In other words, how deep a water-retentive layer >> should I make? >> >> b) How deep should I plan for the bulbs themselves to dig? I forget >> which species dig in more than others, but I recall some of them pull >> themselves deeper each season. > > _______________________________________________ > pbs mailing list > pbs@lists.ibiblio.org > http://pacificbulbsociety.org/list.php > http://pacificbulbsociety.org/pbswiki/