We're lucky enough to live less than a few miles from the Los Angeles Arboretum and Botanical Gardens in Arcadia, California and I am proud to say it's one of the nicest botanical gardens I've ever seen! Divided into geographical and climatic reasons and handsomely interspersed with custom art,  this spot will attract nature lovers for ages to come (though they may be few and far in LA!). 

These pictures were taken on 4th of July under a 90+ degree sun. As you can see many of the plants featured in the images above are relishing the heat. I was very excited to see the Grevillea hedge–a favorite and commonly used landscape design feature of mine–teaming with bees, butterflies and hummingbirds. These low-water almost year-round flowering plants are near miracles for Southern California gardens. They provide a sweet nectar that can be made into a honey-like drink or left for the birds. 

The Canary Islands garden was particularly fetching. A number of the most commonly used landscaping plants in Southern California hail from this tiny, biologically diverse haven. Plants like Canary island pine, sea lavender or statice, Echium (i.e. Star of Madeira), bougainvillea and many aloes climaxed in biodiversity on this unique African island habitat. Here in Southern California, they're right at home with the hot weather and dry conditions. 

One last striking drought-tolerant garden border worth mentioning: the walkway to the art garden lined with fire poker (kniphofia), Mexican sage and yucca.  The dramatic contrast of orange and purple flowers along with the complimentary lance-like foliage forms of the plants makes for a truly inspiring, incredibly low maintenance [and low-water] drought tolerant garden design. 

Growing vegetables in a hot climate (like our Los Angeles summer) is no small feat! Raising seedlings in extreme heat requires some strategy and forethought not required in moister or more Northerly climates. 

How to be successful farming in the desert? 

Here's a few tricks to help your harvest boom in a hot dry climate: 

1. Garden in the Shade

While it may sound counter-intuitive, planting your vegetables in partial or dappled shade significantly improves their ability to retain moisture and handle intense sunlight. The power of a 100 degree sun rapidly evaporates and wilts most plants, but with the help of a supple tree canopy the heat becomes much more bearable. Gary Paul Nabhan, author of Growing Food in a Hotter, Drier Climate routinely has success with this method in the deserts of Arizona. As you will see in our Youtube video, here in Los Angeles we are also seeing remarkable results!

2. Water from Below

Watering from beneath may sound unusual but it is one of the most effective methods for conserving water when growing food. A variety of companies are now producing "self-watering pots" or raised beds but having your water source elevated can also cause rapid evaporation in hot climates. Our solution? We built a sunken reservoir (using poly, landscape fabric and gravel) beneath our vegetable garden that we water through a french drain or weeping tile above. A thorough tutorial on this project is in the works. 

Whatever your resources, adding a water basin below your vegetable garden is a surefire way to save on water and ensure your success. We only have to fill our reservoir about once a week, even in 100+ degree weather!

3. Mulch

I've said it before and I'll say it again, MULCH MULCH MULCH!! The top layer of soil is some of the most crucial for plant root development. Mulching the surface of your soil with straw, wood chip, leaves, shredded paper, rocks or any other organic material is a must in hot climates. Especially if you are overhead watering. 

Here's a quick video of our companion-planted vegetable garden:

The world's most rapidly depleting natural resource isn't fossil fuel and it's not fresh drinking water either... or coal or wood... Believe it or not our planet's most endangered natural resource is top soil! 

What is Topsoil? 
Topsoil is the soft fluffy clean-smelling layer that most plants prefer to grow in. Also called loam, it's very different from the fine, compact sand or clay that usually exists a foot below it. Overtime, the decomposition of natural materials (leaves, bark, wood etc.) by a variety of microscopic micro-organisms causes topsoil to be born. 

On average, it takes around 500 years for nature to produce 1 inch of topsoil. Right now we are washing away this precious commodity anywhere from 10-40 times as fast as the planet is producing it! The biggest culprits? Erosion, tilling, and unnatural waterway management. In the last 4 decades we've lost around 1/3 of viable cropland on the planet due to topsoil loss. 

The Culprits
Heavy tilling of fields and commercial farming causes topsoil to be degraded, pulverized and blown away by the wind. Poor drainage design on roads, pathways and building sites causes topsoil to be washed away by rains. The paving of drainages and waterways means that once it's washed away, instead of being caught in a meandering stream or river course and re-absorbed into the environment, topsoil goes straight out to sea. 

AMAZING Qualities of Topsoil

In the book Terra Preta: How the World’s Most Fertile Soil Can Help Reverse Climate Change and Reduce World Hunger, Ute Scheub and co-authors claim increasing the humus content of soils worldwide by 10 percent within the next 50 years could reduce atmospheric CO2 concentrations to pre-industrial levels. - David Suzuki

Topsoil is also AMAZING at retaining moisture. Cultivating topsoil in the desert (or anywhere) can lead to a 100x the retention of rain water or manual watering, just in a flat field or garden. 

Inspiration

We've put together a short and inspiring video on one of the fastest ways to help generate topsoil. The solution? MULCH

Straw mulch, bark mulch, paper, leaf, bark or even stick mulch will all help to stimulate the topsoil generation process. Leaf blowers beware, you're not wanted here! 

​Without further ado....