Dudley brittonii “Giant Chalk Dudleya”

dudleya brittonii

Image: Annie’s Annuals.

The Annie’s Annuals and Perennials catalog has, as the hip kids say, “dropped.” and I’m wishing we had more space for some of the amazing plants shown on all those glossy pages. One, in particular, caught my eye: Dudley brittonii “Giant Chalk Dudleya.” Just imagine spotting this plant under the light of a full moon.

Annie notes that Dudley brittonii requires excellent drainage, can be grown in pots and is suited to USDA zones 9 to 11. Given our Arrakis like conditions here in California, an excellent bonus is that this plant does well with only monthly water. It also thrives in a pot. Mature, it’s around 18 inches across.

Annie’s does mail order and we’ve had a lot of luck with their plants. I visited the nursery on a blogger junket last year and was very impressed with the variety and quality of the seedlings–no root bound plants!

Now I’ve got to remind myself that a garden needs to be viewed from an overall design perspective, not as collection of pretty plants. Maybe there’s a place for Dudley brittonii  in our garden but it will have to work with what is already there before we, as the hip kids also say, “swoop” one.

World’s Largest Kale

bigkale

The Franchi kale (collard?) “Galega De Folhas Lisas” I planted in the fall of 2012 has reached six feet. It’s a Portuguese variety used in a soup called Caldo Verde.

Given that we have such a small yard I’ve really got to stop planting gargantuan vegetables like this and those ridiculous Lunga di Napoli squash. Root Simple is at risk of devolving into a geek with large veggie Tumblr site.

Hügelkultur in dry climates?

Hügelkultur, popularized by permaculturalist Sepp Holzer, is the practice of burying logs in a mound to create a raised bed that composts in place. As the logs break down they add organic matter and create, in theory, a rich soil full of air gaps, fungal and microbial life.

But the thought of mounding anything in our dry climate doesn’t make sense to me. As I said in my post about the pros and cons of raised beds, if I didn’t have contaminated soil I’d grow my veggies in the ground. A Root Simple reader from Cyprus, which has a very similar climate as ours, said that Hügelkultur experiments there had not worked out. I’ve also heard that Geoff Lawton is skeptical of the practice in dry climates. And I’ve found no peer reviewed research on the practice.

But I also want to keep an open mind. I get asked about this practice a lot and have to confess ignorance. If you know of a Hügelkultur experiment in a dry climate please leave a link. Perhaps there’s a dry climate variation?  Has anyone seen any research? Have you tried it yourself?

Phytoremediation of Heavy Metals

ArtemisiaVulgaris

Mugwort (Artemisia vulgaris)

Us city slickers have fouled the sandboxes we play in. Find an open field in a big city like Los Angeles or New York and the odds are that it’s a former toxic waste dump. Here in our neighborhood we’ve got a lot of lead and zinc–lead from paint and gasoline and zinc from brake linings.

These heavy metals don’t magically go away. They are elements, and short of an alchemical transformation you have to physically remove them, cover them up, or apply phosphate so that plants don’t take them up as readily.

One promising strategy is phytoremediation, the use of plants to uptake heavy metals. City Atlas youarethecity, in New York, is experimenting with Indian mustard, mugwort, basket willow and sunflowers to remediate a contaminated garden. The results are promising with some metals down 50% in a year. Mugwort (Artimesia vulgaris) did an especially good job with a wide range of contaminants.

I should note that Garm Wallace, who runs Wallace Labs, a soil testing service, says that phytoremediation can take many years to get heavy metals down to a safe level. That being said, breeding plants specifically for heavy metal hyperaccumulation is a technology that could make up for our past transgressions.

Thanks to Michael Tortorello for the tip.

How to Search for Science-Based Gardening Advice

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Agricola’s search page.

In the course of writing our books and this blog we’ve had to deal with a lot of thorny gardening questions such as the effectiveness of double digging, the toxicity of persimmons, compost tea, lasagna gardening and how to mulch to name just a few. While the internet is an amazing tool, the number of conflicting commercial interests, biases and crazy talk in the eGardening world can make it difficult to, as Mark Twain put it, “corral the truth.” And I have to confess to promulgating some of the questionable advice that’s out there.

In the interest of not spreading more bad information Linda Chalker-Scott, Extension Horticulturist and Associate Professor at Washington State University, did a webinar (archived online here) with a lot of great advice on how you can evaluate gardening advice as well as do your own searches of peer reviewed literature.

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