Summer moisture, was Hesperantha vaginata

Jane McGary
Thu, 25 Oct 2012 16:59:37 PDT
I agree with Peter and Shmuel that summer moisture for potted bulbs 
should be just enough to maintain a little humidity in the medium, 
not the thorough watering that Jim Jones seemed to be describing. If 
I think my bulbs might get too dry, especially when I used to grow 
them in plunged pots, I would just "wave" the water wand over the 
area briefly. A real soaking will either rot the bulbs or start them 
into root growth prematurely, and then subsequent drying will harm 
them or indeed kill them. I never soak mine until cool, damp weather 
arrives in autumn. These are, of course, all summer-dormant species.

I'd add that seedling bulbs may tolerate more summer water than 
mature ones. I just potted on a lot of Fritillaria amana (yellow 
form) seedling bulbs that I had inadvertently left in a flat that was 
watered regularly all summer, and they look fine.

Shmuel mentioned "dew" providing moisture to dormant Chilean bulbs. 
In the case of the wonderful bulbous flora of the northern coastal 
region, it is actually fog, the camanchaca. Like Namibia in Africa, 
the Atacama region of Chile is a "fog desert." (In some inland parts 
of it there are no plants at all, ever, except perhaps where seeds 
are dispersed by road traffic.) However, the bulbs that grow there 
don't even emerge unless they experience actual rainfall and runoff, 
remaining dormant for years continuously until that happens. There 
are some sclerophyllous shrubs that grow and even flower a bit in the 
dry years, and they are adapted to trapping the moisture from the 
fog. Like some of the bulbs I saw in Jordan, the Atacama bulbs tend 
to have very thick, persistent tunics with a number of layers. Also, 
they can be very deep in the ground.

Jane McGary
Portland, Oregon, USA


More information about the pbs mailing list