Keyhole sun catch in central FL....what was I thinking?!

I'm new here and relatively new to permaculture...trying to catch up.

I set up a south facing keyhole raised bed in my garden.  (the open end faces south)
The "u" has walls about 3' thick and about 2' high.  Lots of organic material. 

I'm in zone 9 ish and my thinking was this would catch sun, give me lots of edge, and pour off the cold on the nights we freeze here.  I still think that will be the case, but...what about the warm (ok frigging HOT) days?  I cooked all my fall starts today, and all the awesome organic material was dry as tinder in the keyhole but still nice and moist in my traditional raised beds. 

Not sure how to keep it warm on cool nights and cool on hot days...I need a garden thermos lol

What am I missing?  Rookie mistake? I appreciate any advice, Thank you.

Hey,

just a thought,
a thermal mass (like a very big rock/stone, or waterbody/pond) will temper extremes: when hot, it aborbs the heat; when cold it will radiate warmth.

Joop Corbin - swomp wrote:
Hey,

just a thought,
a thermal mass (like a very big rock/stone, or waterbody/pond) will temper extremes: when hot, it aborbs the heat; when cold it will radiate warmth.

Thanks! Makes sense (sort of)  I've tried water barrels to keep an area warm on a cool night, I'me having a hard time wrapping my head around the large rocks keeping it from getting too hot.  I would have assumed you add rocks for adding heat, but it took me a bit to grasp the whole concept of adding rocks to increase moisture too.

Thermal mass is good but only works if shaded during the hot weather.  Otherwise it will heat up to buggery and cook your plants even better.

I'd be thinking of open-canopy trees to solve this problem, i.e. those that will give a little bit of shade but not too much.  Deciduous if possible to still get all the winter gains you talked about.  However they are not an instant solution

Hugh H. wrote:
Thermal mass is good but only works if shaded during the hot weather.  Otherwise it will heat up to buggery and cook your plants even better.

I'd be thinking of open-canopy trees to solve this problem, i.e. those that will give a little bit of shade but not too much.  Deciduous if possible to still get all the winter gains you talked about.  However they are not an instant solution

Awesome!  And I know just the tree! Thank you!

By the way, we spent some time in Adelaide on our honeymoon...nice place great memories and tons of wine! . Thanks again!

Not many plants actually like "full sun" (8-10 hrs) in anything hotter than a cool temperate climate, in my experience.

You could use a piece of light shade cloth like a sail to protect your plants while the trees grow.

Good to hear you sampled some of our best product

Alex B. wrote:
...  and all the awesome organic material was dry as tinder in the keyhole but still nice and moist in my traditional raised beds. 

For better or worse, a raised mound has more surface area exposed, and it will 1) heat up and cool down faster when the temperature moves in one direction, and 2) dry out faster compared to a flattish raised bed. It might also absorb less water, as the slope will shed water in a summer downpour. In cool/moist conditions, the raised surfaces are an advantage; in a hot/dry conditions, the swales in between the ridges are more favorable.

Once a tree is established, it can do ok in either the hill or valley of a micro-topology. Even with good design, a period of drought or low rain can take a toll - just less of one initially, as good designs are buffered and more stable, but not insulated from the elements.

We are building a 22 acre permaculture farm in South Florida and are just finishing our 3 acre food forest design. In our design we made a couple sun traps facing magnetic south for our cold tender tropical plants. However, summer time that whole area would be cooked with the high heat that we get. We placed trees that are deciduous that lose there leaves, like mamey, and are not completely frost tolerant in the middle of the sun trap. Come winter time, we have an open sun trap warming up all the plants that need to be warm. Once the summer time comes, there is a normal canopy happening and there is no sun trap effect.

Depending on your design of what the keyholes purpose will be for, maybe you can set a deciduous tree in front of it, an awning with grapes, or something of that sort. Or, maybe just plant your heat loving plants there that grow well in the tropics and disregard your european vegetable crops.

Also, most likely the seedlings need a little more protection in their early stages.