Permaculture on Sandy Soil - Help!

hey,

i recently bought a 40m x 40m plot of land in coastal Brazil and want to start a permaculture garden.....but i need your help!!

the location of the land is just north of the equator in a place called Natal.......
the average mean temperature is 26C and the area gets about 55 inches of rainfall / annum  - here's a wikipedia link for more details on the climate.....

http://en.wikipedia.org/wiki/Natal,_Rio_Grande_do_Norte

ive taken a few pictures of the wild/natural state of the land and soil as it is now......amongst the fruit trees native to the region that grow wild are:

coconut palm, acerola, acai, paw paw, cashew and caja fruit ......... i would like to grow all of these........

i would also like to grow things like citrus, mango, avocado and passionfruit......

here's links to pictures of the land and soil.......


https://picasaweb.google.com/dr.demodex/Mar92011#5584517417599147954
https://picasaweb.google.com/dr.demodex/Mar92011#5584517559104416466
https://picasaweb.google.com/dr.demodex/Mar92011#5584517729738720274

so, basically, what do i do???! do i need to do anything with the sandy soil? blanket cover the whole plot in nitrogen fixing legumes first? or is it fine the way it is, because the fruit that i want to grow does well in this climate and sandy soil?


any suggestions and help is greatly appreciated!!

cheers

If you haven't already viewed this video( http://www.youtube.com/watch?v=3vfuCPFb8wk ), I recommend that you watch it.  It can give you some good ideas on what to plant as it is in the same type of climate.

With 55 inches of rain the soil nutrients have been and will be washed out.  I would plant some of the native fruit/nut trees with a nitrogen fixing and biomass accumulator understory, with ground covers and deep accumulators.  Trying to increase the organic matter in the soil ,in that climate, is a losing battle as it is broken down as fast as it is created. 

Is there a dependable water source beside rain fall?  If not, you will need some type of water storage (pond?).  If a pond is not an option, you could try a mulch pit ( a pit filled with mulch then trees plant around it).

David Wise, DaBearded1

wonder if you could find a source of clay to mix in to some of your sandy soil, also add as much humus as you can ..(some kitty  litter is clay based??)..I'm not too familiar with your climate as I'm from Michigan USA

DaBearded1 is right - in wet tropical climates, most fertility is not stored in the soil, but in the plants. Tropical rainforests have very poor soils. Put in the trees and shrubs that you mentioned - coconut, mango, etc. Use legumes to fix nitrogen, along with other dynamic accumulators, but cut these to mulch the shrubs and trees. You could 'chop and drop' with large, deep rooted legumes, or 'mow and throw' if you plant clover or other shorter legumes - not sure what is best in your area.

Before planting though, go to a naturally forested area near your property and observe the plants at grow around the type of plants you wish to grow.  This will give you an idea of the plants you need for your poly-cultures.

And a soil test, for Ph and salt levels.  Because if the Ph is to far one way or the other, it will need to be brought into balance.  You mentioned that the land is coastal so you may have high levels of salt which will cause problems.

David Wise, DaBearded1

Hugelkultur might be a good way to get a lot of organic material into the soil in a hurry. 

thanks for all the replies - lots of food for thought!


the land is about 700 meters inland so i dont think salty soil is really an issue...that part of the world has on average 300 days of sunshine/ year and NASA has also done a study reporting that the air is the cleanest on the planet (after antarctica)......

the developer of the site has drilled into the land looking for good quality water to provide to residents of the development and a good source has already been found..... ( its a gated community with 46 plots of land - i bought 2 plots beside each other - a total area of roughly 40meters x 40 meters or 1600m2)

the development wont be finished until the end of 2012, and i wont be ready to build on the land for another 3 years or so........so, what i wanted to do in the meantime was to go over and just spend a few weeks establishing a permaculture garden on the land and just let nature run its course while im away (i have business in europe and asia so i wont be in brazil very often until im ready to build and live there) ........

http://www.aprovecho.net/

Although based in oregon, folks from Aprovecho have been studying bio-char in Brazil.

You might find info there.    cheers

Definitely check out the biochar.  I'm in central florida on very sandy soil with heavy summer rain.  I've been mixing char with my compost that I add to the garden.  It should hopefully reduce the nutrients that are leached out.  I'm only a year in so I don't have any results yet but from what I read it seems promising.

Good luck

In that climate/soil, nutrients will wash out quicker than they would in an arid clay environment.  Adding LOTS of organic matter will endure longer than minor portions would.  Adding a lot of biochar would certainly help...it is absorbant, and will collect and hold a lot of the nutrients that would ultimately end up in the water table beneath.

With some early planning, your plot should provide you with abundant food.  The avacados I bought in Porto Natal were huge and delicious.

Boa sorte

mamaturkey Hatfield wrote:Definitely check out the biochar.  I'm in central florida on very sandy soil with heavy summer rain.  I've been mixing char with my compost that I add to the garden.  It should hopefully reduce the nutrients that are leached out.  I'm only a year in so I don't have any results yet but from what I read it seems promising.

Good luck

Just found this post. I have been working on my yard for about a year now in Central Florida. I have been adding compost, which seems to be doing well. Do you find that the char is helping you retain the nutrients in your compost? I ended up fertilizing once last year and would like to avoid it this year entirely. I know I can just dump more compost on it but if the char will extend the nutrients that would probably be more cost effective (and efficient).