Raised beds and capillary action

Antennaria@aol.com Antennaria@aol.com
Tue, 06 Jul 2004 19:23:40 PDT
"Rodger Whitlock" totototo@pacificcoast.net wrote:
>E B Anderson, the famous English rock gardener 
>and bulb specialist, grew his summer dormant bulbs 
>among (or near) the roots of deciduous trees. As the 
>trees leafed out in late spring and the roots became
>active, they would suck the soil around them bone dry.

I can attest to this methodology of growing bulbs... I use it extensively.  I 
make large circles around the base of some deciduous trees and shrubs, and 
underplant with a large array of hardy bulb species.  As the theory goes, the 
active growth of summer growing trees and shrubs siphons off moisture in the 
summer months, and the deciduous nature of the shrub/tree in late winter/early 
spring allows early spring growth of the bulbs.  To take this even a step 
further, I underplant with late-leafing trees and shrubs, such as single-flowered 
forms of Hibiscus syriacus, the native fringe tree Chionanthus virginicus, and 
the native Sourwood tree, the gorgeous Oxydendron arboreum (see link):


I have also underplanted Stewartia pseudocamelia (in glorious bloom right 
now), Magnolia denudata 'Forrest's Pink', and Cornus kousa 'Milky Way'.  The 
Stewartia has intense surface roots that inhibit underplanting (thus not 
receommended for underplanting), the deeply rooted Magnolia works splendidly to host 
Trillium and other bulbs, and the Cornus is a bit too densely leafy unless 
aggressively pruned to allow more light and moisture in.

I have also used raised beds to good effect.  These are not contained in any 
way (with hard wood edges or restraints, further constraining misture 
content), but are merely raised mounds of very sandy soil open to the elements.  I do 
use mulch, and find it helps moderate the extremes, but have not been as 
diligent as I should about replacing lost or decomposed mulches.  In these raised 
mounds, I have grown Juno Iris to great success, and even tried a couple of 
Oncocyclus Iris out in the open, with very good results.  None are protected, and 
get rained on, and some irrigation.

Lastly, I have an experimental bed that I've been very pleased with.  I have 
no end of losses and badly conceived irrigation trials, but one that has 
succeeded is a "western bulbs" bed, in which I planted some of Jim Robinett's bulbs 
(Brodiaeas, Triteliaeas, Allium, Calochortus), then included some Juno Iris, 
and an Eremurus (obviously non American, but sharing similar needs?).  The 
idea, was a layer of clay soil amended with considerable sand, about 8" deep, 
over a layer of unamended heavy rocky clay (my native soil here).  The idea is, 
the bulb roots get into the clay layer and derive the moisture they need, yet 
have sufficient drainage around the bulbs themselves, to avoid rotting.  This 
bed has been a great success for the most part, and I'm encouraged by Trits, 
Frits,  one Calochortus, and other bulbs in expansion mode, seeding around.

Mark McDonough Pepperell, Massachusetts, United States 
antennaria@aol.com "New England" USDA Zone 5
>> web site under construction - http://www.plantbuzz.com/ <<
alliums, bulbs, penstemons, hardy hibiscus, western 
american alpines, iris, plants of all types!

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