Courtesy of Steele County Master Gardeners

I used to go to the big box stores and browse the fertilizer aisle looking for the one that “instantly turns your lawn green” or “promotes fabulously spectacular blooms” or “produces state-fair winning veggies.”  Marketing is a seductive thing.

I knew those three little numbers, 00-00-00, meant something, but left their interpretation up to the professionals.  Turns out, those numbers–what we call N-P-K–are pretty important.  They reflect the key nutrients that soil needs to do its job of making things grow.

In a perfect world, our soils would contain every nutrient in the right proportion to grow whatever we wanted to grow.  And all soils would be the same.  But we live in the Phoenix desert where our typically alkaline soils lack sufficient quantities of nitrogen.

Fortunately, many of our native and desert-adapted xeriscape plants are actually “nitrogen-fixing”–that is, through a  highly efficient chemical process, they produce the nitrogen they need to thrive.  Most legumes, the bean- or pod-producing plants, are excellent nitrogen fixers and include desert favorites:  mesquite, palo verde, ironwood, acacia, senna, and many more.

But where native and desert-adapted plants require no fertilizer, non-native plants need nitrogen and other nutrients just to have a fighting chance at thriving here in our desert gardens.   Turf grasses, roses, citrus, and most other edibles need extra help in the form of fertilizer.  And that’s where N-P-K, or nitrogen-phosphorus-potassium, come in.

Coming next…part 2, the demystification of fertilizer!

And while we’re at it…the Boyce Thompson Arboretum is having its spring plant sale through March 25, 2012!

(I won’t get into how dang lucky we are to have not one, but TWO major gardens in the Phoenix area! Each offers a completely different, but equally excellent experience.)

Anyway, if you’re into desert gardening, then pick up some xeriscape plants at the Boyce Thompson Arboretum. Plant sale hours coincide with arboretum hours (8:00am to 4:00pm daily) and runs through March 25.  I’m sure they’ll provide gardening tips, too, and members do receive 20% off plants.  Another good reason to join!

I have boatloads of space for vegetable gardening, and can easily expand if I need to.  But if you’ve got a small space, you can still plant vegetables and herbs in raised beds, boxes and containers–even in the desert!

A friend just pointed me to the Monarch Garden Box, a really great idea for a small space.  Made locally here in Arizona, these boxes stand around 3 feet high, making them easy to work in.  They’re generously sized at 4′ x 2′ with a 12″ depth and they’re made from pest- and rot-resistant redwood.  I believe they’re also on wheels so you can easily move them around.  (Or wheel it around the neighborhood to show off your prized veggies!)

Add some good quality soil and, with some good planning, you can get more than a few plants in these guys for a steady supply of fresh stuff!