A Cheap Soil Testing Service

I’ve started a new method in the garden: test the soil, amend according to the recommendations and grow. Lather, rinse, repeat. In many parts of the U.S., you can get free or low cost soil tests from your county extension service, but not here in Los Angeles. Some time ago I answered a reader’s question about where to get soil testing done, only to have to correct my response several times. Last week, Homegrown Evolution pal and the editor of Cool Tools, Elon Schoenholz, gave me a definitive answer on where to send soil for testing: the University of Massachusetts Amherst, Department of Plant and Soil Sciences Soil and Plant Tissue Testing Laboratory. A standard soil test is $9, $4 more for the standard test plus organic matter. The standard tests includes heavy metals. That’s a bargain, and you don’t have to be a resident of Massachusetts. They also offer compost, fertilizer and plant tissue tests at reasonable prices.

Read a review of UMASS soil testing by master gardener Amy Thompson at Cool Tools.

My Big Fat Greek Squash


Every time I visit my mom, her Greek neighbor pops over the fence to offer me seeds and plants. He visits Greece each summer and comes back with seeds for plants whose names he can’t translate into English. As a result I always have a few mystery Greek vegetables growing in the garden. This spring he gave me a squash seedling he had propagated. It grew into a massive vine and produced two winter squashes whose weight exceeded the capacity of my kitchen scale. I harvested them last month and we’ve been eating a lot of squash!

The skin turned a kind of manila envelope color and the flesh was a deep orange. It kind of looks like a butternut squash on steroids. The flavor resembled pumpkin, but tasted a lot better than most pumpkin I’ve had. We roasted one squash to make squash tortellini among other dishes. The best recipe, however, was for a savory winter squash pie (galette) out of Mark Bittman’s book How to Cook Everything Vegetarian (thanks to Bruce of the Green Roof Growers for suggesting this book). Bittman’s spicy winter squash galette recipe is here on MSNBC along with a video of him making it. I’ll note that the online recipe is different from the one in the book which calls for a longer baking time. My galette was in the oven for over an hour, but I did not cook the squash as long in the frying pan as Bittman does in the video. I’m sure either way will work, and this has to be, seriously, one of the best things I’ve ever cooked. It would make a great substitute for the always dry Thanksgiving turkey.

And I’ve made a mental note to myself to grow more winter squash next year. I like the taste better than summer squash and you can store it in the pantry for later use (hence the “winter” in the winter squash).

If you’d like to hazard a guess as to what this squash is called (especially if you’re Greek), please leave a comment.

The End of California Citrus?

As small as an ant, the Asian citrus psylid is big trouble!

When I spotted state agriculture agents on our street I knew something was wrong. It turns out that a specimen of the dreaded Asian citrus psylid showed up in our neighborhood. The Asian citrus psylid is not a problem in itself, but carries an incurable bacterial disease called huanglongbing (HLB). HLB, first reported in Asia in 1919, renders citrus fruit inedible and eventually kills the tree. Parts of Africa, Asia and South America are infected with HLB and in some regions of Brazil the disease is so bad that they’ve given up growing citrus altogether. HLB is in Florida and is adding to a nightmarish collection of other diseases afflicting citrus in the Sunshine State. Now California growers are panicking with the appearance of the psylid.

So far the psylids found in California do not carry HLB. However, according to an article in the Journal of Plant Pathology (pdf), HLB inevitably follows the citrus psylid within a few years. In several ways HLB resembles Pierce’s disease which has killed most of my grape vines and basically made growing table or wine grapes in Southern California impossible without copious pesticide application. Both diseases are bacterial and both are spread by phloem sucking insects. The pesticides used to control the Asian Citrus Psyllid and the Glassy Winged Sharpshooter (the insect that spreads Pierce’s disease) are also the same, and include a ground application of imidacloprid, marketed under the brand name Merit and manufactured by Bayer Environmental Science. State agricultural officials that I spoke with at an informational meeting on Wednesday in Echo Park hope that applications of imidacloprid and pyrethroids will slow the progress of the psylid and, “buy some time”, as they put it, to come up with a strategy to deal with the possible appearance of HLB. California agriculture officials hope that their proactive approach combined with lessons learned from missteps in psylid control in Florida and the rest of the world will slow the progress of the insect and minimize the damage of an emergence of HLB in California.

Compliance with the residential pesticide application program is voluntary. State agriculture officials will knock on the doors of residents in three areas in Los Angeles where the psylid has appeared to ask for permission for a foliar application of pyrethroid and a ground application of imidacloprid to any citrus trees a homeowner might own.

While I understand the gravity of the situation–we really are looking at the possible end of citrus in California if HLB gets a foothold–the use of imidacloprid gives me cause for concern. Imidaclopred is highly toxic to honey bees and has been banned in several European countries for its likely connection to colony collapse disorder. When I told an employee of the Department of Pesticide Regulation at the meeting on Wednesday that people in my neighborhood keep bees he paused and said, “you’ve got a problem.” Another official said to me that our bees (and presumably other pollinators in the neighborhood) will be sacrificed for the greater good of preserving the state’s citrus industry.

As with Pierce’s disease the best long term solution to this problem will be to breed trees resistant to HLB. This is easier said than done as, unlike Pierce’s disease and grapes, no HLB resistant citrus cultivars have been found. It may be that the only way to breed for resistance soon enough to head off the HLB will be through the development of transgenes with antimicrobial properties. This approach is already being funded by the USDA and the citrus industry.

As a backyard gardener and rabble rousing blogger, I could lose a lot of sleep pondering all the thorny questions this crisis brings up. Are there situations where genetic modification is warranted, or do antimicrobial transgenes pose unintended consequences? Will localized applications of imidacloprid kill our pollinators in significant numbers or will strategic applications head off more widespread use later on if nothing is done? What are my responsibilities as a backyard gardener to large scale growers? Do the benefits of international trade outweigh the inevitable appearance of invasive species? Should we close the downtown flower markets and produce distribution warehouses where state entomologists suspect the psylids might have come from?

Rather than try to answer the unanswerable, I’m going back to two of my favorite books books that don’t have anything to do with plants. Nassim Nicholas Taleb’s The Black Swan: The Impact of the Highly Improbable, a meditation on the logical fallacies of economists and Seneca’s Letters from a Stoic have all the strategic wisdom a gardener needs. Seneca would say, do what is in your power to do and don’t worry about what you can’t fix. Taleb would advice always maximizing upside potential while minimizing exposure to the downside. My unsentimental conclusion: don’t try to grow citrus. If I had a mature tree I’d leave it in place and rip it out at the first sign of HLB. Despite the state’s offer to replace any HLB infected tree with a free citrus tree I wouldn’t take them up on the offer. In our case we have three small, immature citrus trees that are already chewed up by citrus leafminers. I’m pondering pulling them up and replacing them with fruit trees unrelated to citrus. This follows our stoic, get tough policy in the garden. Planting a tree entails a considerable investment in time. It can take years to get fruit. Why not plant pomegranate instead and let other people worry about citrus diseases? If a pomegranate disease shows up, rip it up and plant something else. Following this approach will eliminate habitat for the psylid and negate the need for pesticides.

Orange v. Tuna ¿Quien es Más Macho?

The first consideration with any domestic plant or animal should be choosing species with robust immune systems and then following that up with an objective selection process. This is an approach that mimics one of the fundamental laws of evolution: survival of the fittest. True, there is often a trade off between the flavor and yield of a fruit and strength of its natural defenses. Oranges are juicier and easier to peal than the spiny and seed filled fruit of the prickly pear cactus. But the long term odds of having a reliable supply of prickly pear fruit are a lot higher than a steady flow of orange juice. I may get a few spines in my fingers, but it will be the citrus farmers who will be losing sleep. As Seneca says, “If you shape your life according to nature, you will never be poor; if according to people’s opinions, you will never be rich.”

View a video on how to recognize Asian citrus psylids here.

Urban Farm Magazine

We have a article on urban farmers across America in the premiere issue of a magazine bound to appeal to readers of this blog, Urban Farm. Our article, Where Urban Meets Farm, profiles the efforts of our friends the Green Roof Growers of Chicago, Em Jacoby of Detroit and Kelly Yrarrazaval of Orange County. All of these fine folks have repurposed urban and suburban spaces to grow impressive amounts of food, a common sense trend popular enough to have spawned this new magazine.

Editor Karen Keb Acevedo says, “Urban Farm is here to shed a little light on the things we can all do to change our lifestyles, in ways we think are monumental as a whole, yet at the same time, barely noticeable on their own.” The first issue has practical articles on goats, bees and chickens as well as how to get rid of your lawn. There’s also a nice article by John Jeavons, who developed the Grow Biointensive method, and wrote the seminal book How to Grow More Vegetables and Fruits.

Check your local newsstand for Urban Farm or pick up a copy of the premiere issue here.

Hops in Containers

This spring I set out to answer the question, “can hops be grown in self-irrigating pots?” Answer, as you can see from the photo above: YES! For those of you not familiar with Self-Irrigating Pots or SIPs we have an earlier post on the subject.

Hops rhizomes, planted April 9, 2009

For our hops SIPs I modified a storage bin using Josh Mandel’s instructions (pdf). Back in early April, I obtained four hops rhizomes (two cascade and two nugget) from my local homebrew shop. You can also get rhizomes from many online sources. I chose cascade and nugget because I heard that they are two of the best varieties for Southern California. Both did well, with cascade being the most vigorous. The smell of the maturing cones is heavenly and the plant is quite beautiful, providing some much needed shade for the porch.

Nugget on the right, Cascade on the left

The only suitable place to grow this massive plant at our small house just happened to be by the front porch. This arrangement ended up being ideal–we’re on a hill and I simply attached some twine along the roof and put the SIPs down below the porch. I can simply stroll out on the porch and harvest the blossoms without having to balance on a tall ladder. Having the hops cones at eye level lets me access the cones when they are ready to pick and lets me monitor the health of the plant. I’ll also to be able to continuously harvest rather than having to cut down the entire plant. Alternately I’ve seen hops trellises rigged with pulleys so that you can lower the “bines”, as they are called, for harvesting.

Hops farmers in England demonstrating why you need to think about trellising.

With a western exposure the hops get morning sun and shade in the afternoon, which seems to be perfect in our sunny, dry and hot Southern California climate. The only problem I’ve had is a bit of rust, but it doesn’t seem to have spread too badly. Hops suck up a lot of water and, thanks to the SIPs, I only have to water once a day.

The SIPS are full of potting mix with a ring of organic fertilizer placed on top of the soil as specified in Josh Mandel’s directions. I have periodically added an organic liquid fertilizer to the water reservoirs as hops need a lot of nitrogen.

Cascade cones almost ready to harvest in late July

I don’t know how my hops will do in SIPs the second year, and I’m considering planting them in the ground if I can find a suitable place. I suspect that hops are a good candidate for pairing with a greywater source and I’m thinking about ways to do this.

Now that I’ve grown hops, I’m tempted to go to the next level. The local Rite Aid? How about we replace it with a field of barley? I’m anxious to swing a scythe again.

Stay tuned for info on a hops growing workshop with Boris Price and the folks at Silver Lake Farms to be hosted at the Homegrown Evolution compound this month. Look for the announcement on our blog this week.

Author and Urban Farmer Novella Carpenter Rocks Los Angeles

Yesterday, Homegrown Evolution had the great privilege of meeting urban farmer and author Novella Carpenter who was in Los Angeles to deliver a lecture and sign her new book Farm City. She’s a phenomenal speaker, both hilarious and inspiring. What we like most about Carpenter is her honesty in describing the ups and downs of raising pigs, goats, chickens, turkeys, rabbits and more on squatted land next to her apartment in Oakland. As she put it, “I don’t like to sugarcoat things.” As owners of a garden that is often a little rough around the edges, we were inspired by this photo of her squated garden that she showed during her lecture. We could have listened for hours to her stories of dumpster diving for pig feed, gardening in a neighborhood where “crack zombies” and prostitutes come out at night and how the local Yemeni liquor store owner came over to show her how to slaughter her mean goat. If you have a chance to hear her speak, make sure to go!

We’ve read excerpts from Farm City and Carpenter is a terrific writer. In addition to her books and articles she blogs at ghosttownfarm.wordpress.com and offers workshops on raising and slaughtering animals for meat in the city. And like Carpenter, we also fantasize about trading the bicycle for a mule. Time to print up the “one less bike” saddle stickers . . .

World’s Skinniest Farm Planted in Brookline, MA

From 200footgarden.blogspot.com:

“The 200 Foot Garden is a community garden/art project, to create a commuter garden in Brookline, Massachusetts. Our hope is to add some beauty and delight to a very everyday stretch of sidewalk and chain-link fence. It’s also our hope to remind people that healthy vegetables can be grown in all sorts of environments, not just farms or big yards or community garden plots. The 200 Foot Garden is also a way to bring together neighbors in a project designed to share good things with the people around us.

The project is headed by Patrick and Tracy Gabridge. In our everyday lives, Patrick is a novelist and playwright, and Tracy is a librarian.”

Humanure Dry Toilet Made From a Milk Crate


Modern toilets take two valuable resources, water and nitrogen rich human waste, and combine the two to create a problem: sewage. In a dry or “humanure” toilet, you cover your deposits with a layer of non-toxic sawdust. Once the toilet is full you dump the contents into your outdoor humanure pile and compost the waste at high temperatures for at least a year. You can then use that compost as fertilizer for plants. The ubiquitous five gallon bucket is the most commonly used humanure receptacle. Most humanure toilet designs I’ve seen such as the ones on Joseph Jenkin’s website make use of wood which I’m not crazy about in the wet environment of a bathroom. Even with a coat of paint wood gets grungy. Alternatively, you can buy plastic camping toilet seats that will clamp on to a five gallon bucket but they have, in my opinion, an unacceptable wobble when you sit on them. For these reasons I designed a sturdy dry toilet making use of a scavenged milk crate. Even if the idea of humanure grosses you out (and it’s definitely the most controversial subject in our book), our milk crate toilet would be great for camping, emergencies or your remote cabin.

Putting this toilet together takes just a few minutes. First, find a milk or beer crate and a five gallon bucket. Make sure that the crate you use is large enough to accommodate the bucket. And note, I know of someone arrested for scavenging beer crates behind a strip club, of all places, so be discreet or ask for permission. Incidentally, when the police finished booking the beer crate scavenger the officer placed the paperwork in . . . a scavenged beer crate doubling as an in box!

Attaching the Toilet Seat to the Crate

Next, find a toilet seat. Forage one or pick up a cheap seat at your local hardware store. In an emergency situation, you could also use the one on your regular toilet and simply bolt it back on when the zombie threat has passed and the sewage pipes are flowing again. To attach the seat to the milk crate simply position the plastic bolts and nuts that come with the lid in the center and on the short end of the bottom of the crate. Don’t over tighten.

Cutting Out a Hole in the Crate

Place the bucket so that it will be appropriately positioned under the seat. Mark the outline of the bucket on the crate with a knife and cut out a circle with a jigsaw or keyhole saw so that the bucket will fit through the former bottom of the crate.

Attaching Legs to the Crate with Cable Ties

Cut four pieces of scrap wood (we found some old table legs for a more finished look), and attach them to each corner of the crate so that the bucket projects about a 1/2-inch above the level of the crate. The legs will be approximately 13 1/2-inches. Make sure that the toilet seat will fit snugly against the top of the bucket. We attached the legs with cable ties, but you could also use screws or bolts.

Moving the Spacer

The last step is to move the spacer on the bottom of the lid, so that it does not hit the top of the bucket. Pop it out with a knife or chisel, drill another hole, and reposition.

Your humanure toilet is now done and ready for use. Simply lift the crate off the bucket when it comes time to empty the contents. Follow the detailed instructions on Joseph Jenkin’s website to learn how to properly compost human waste.


This toilet is simple to make, easy to clean, and is made of readily available materials. I think this particular design will be useful in emergencies and, when combined with Jenkin’s excellent humanure methods, would prevent the dangerous raw sewage nightmares of the sort we saw in the aftermath of hurricane Katrina. There is a creative commons licence on all the text and photos on this website so feel free to translate and disseminate this post widely. We’re “open source” here at Homegrown Evolution. If you make an improvement in the design please let us know.

Behold the Glassy Winged Sharpshooter (Homalodisca coagulata)


I finally spotted my first glassy winged sharpshooter (Homalodisca coagulata or GWS for short) sinking its vampire like feeding tube into one of my hops vines. The GWS transmits Pierce’s disease, fatal to many grape varieties including my flame seedless, a gardening frustration I blogged about last week. For your enjoyment I captured a 1/2-inch GWS specimen and scanned it. Note that the GWS was harmed in the process, for which I’m unapologetic.

While there are many varieties of native sharpshooters in California, the GWS is an interloper from the Southeast US and is much more mobile. The native varieties tend to hang out in riparian areas while the GWS enjoys jumping around backyards, citrus groves and vineyards, spreading a host of nasty plant diseases including almond leaf scorch and Citrus Variegated Chlorosis. The GWS is also responsible for spreading oleander leaf scorch. Astonishingly, 20% of home gardens in California contain oleander and 2,000 miles of highways in the state are landscaped with it. The University of California estimates that oleander leaf scorch could cause over $52 million in damage.

Dig the GWS’s built-in hypodermic syringe!

The discovery of a GWS in our yard has solved a mystery that has puzzled us for years. When sitting under the grape vine covering our arbor we’ve often felt little droplets of water, highly unusual in a place where it never rains past April. Turns out it was sharpshooter pee. Sharpshooters feed on the xylem, the water bearing veins of plants. As the xylem contains mostly water, the sharpshooter must process large quantities of material in order to survive. Excess water is puffed out their rear ends, a fascinating thing to see close up. The constant water puffing combined with their fast side to side movements make GWS seem more like machines than insects. Perhaps we could “monetize” this blog by teaming up with Hasbro and Michael Bay to create a line of glassy winged sharpshooter toys, video games and action movies.

Barring a GWS blockbuster we can instead offer our fellow plant and insect geeks an industrial film from the University of California that delves into the GWS in pornographic detail. Nice retro voiceover talent on that video UCTV (one of Mr. Homegrown’s former employers, fyi)!

If you like that video, you’ll also enjoy UCTV’s 90 minute Home Vineyard lecture. I’ll add one point to that talk: if you’ve got GWS, grow muscadine or native grape varieties. Don’t bother with table or wine grapes until the bright folks at UC figure out how to breed Pierce disease resistant vines.

On the Many Frustrations of Gardening: Pierce’s Disease

Damn Pierce’s Disease!

I really wish that glossy gardening magazines would, every once in a while, devote some space to capturing some of the soul-crushing disappointments of tending plants. Can we please have a cover of Sunset Magazine featuring an aphid and slug infested cabbage? Frustrations are compounded when a beloved perennial plant you’ve been growing for years comes down with a fatal disease. Such was the case when my flame seedless grapevine, which was planted to cover our backyard arbor, contracted Pierce’s disease, caused by an incurable bacteria (Xylella fastidiosa) spread by an insect called the sharpshooter. Pierce’s was discovered in 1892 in Anaheim and is basically the reason we no longer have many vineyards in Southern California. Once a vine gets Pierce’s it will die within a few years. You have to admit failure and rip it out, which I plan to do soon.

“Wood on new canes matures irregularly, producing patches of green, surrounded by mature brown bark.”

To confirm that my vine had Pierce’s I called Jerry Turney, plant pathologist at the Los Angeles County Agricultural Commissioner’s Office. When I described the symptoms, Turney agreed that it sounded like Pierce’s. The signs of Pierce’s, as described in UC’s pest management guide, are:

“(1) leaves become slightly yellow or red along margins in white and red varieties, respectively, and eventually leaf margins dry or die in concentric zones; (2) fruit clusters shrivel or raisin; (3) dried leaves fall leaving the petiole (leaf stem) attached to the cane; and (4) wood on new canes matures irregularly, producing patches of green, surrounded by mature brown bark.”

“Fruit clusters shrivel or raisin.”

Turney described the life cycle of the sparpshooter, one of the main carriers of Pierce’s, who spread the diesase by feeding off the sap of infected plants. Sharpshooters live in riparian areas and when a stream goes dry they fly off in search of irrigated plants to feed on. Sharpshooters also like to spend the winter in citrus groves which, while not susceptible to Pierce’s, provide habitat. Our hot dry summers, which dry out local streams and rivers, and abundant citrus trees, make inland Southern California an especially bad place to try to grow grapes. Why nurseries continue to sell vines suseptable to Pierce’s here is a mystery to me.

In the 1990s Pierce’s disease wiped out 40% of the vines in Temecula’s vineyards. Northern California’s vineyards have experienced what Turney described as an “edge effect”, with Pierce’s claiming the vines on the outside of vineyards. The only way to prevent the spread of the sharpshooter is frequent application of pesticides (on both grapes and citrus), not practical for the home gardener and we’re organic around the Homegrown compound anyways. In fact, one of the pesticides used to control shapshooters is Imidacloprid, implicated by many in the recent disappearance of honey bees.

Pierce disease resistant Vitus californica attacking our house.

The only hope for long term control, as Turney sees it, is by breeding hybrid grape varieties resistant to Pierce’s. Turney strongly advised against trying to grow wine or table grapes in Southern California. After losing three table grape vines in ten years, I can attest to the wisdom of Turney’s advice. To grow grapes in the warm southern parts of the U.S., you simply have to plant Pierce resistant varieites such as the native Vitus californica or muscadine grapes. The contrast between our flame seedless and our Vitus californica vine, in fact, is stunning. The flame is stunted and diseased, while our Vitus californica is so vigorous that I have to beat it back on a daily basis to prevent it from subsuming our house and the neighbor’s.

And while we’re working on resistant grapes we may need to start hybridizing citrus as well. While the strain of Pierce’s that took down my grape vine is harmless to citrus, there is a variant of the bacteria that is currently ravaging the citrus of Brazil and Argentina which causes a disease called Citrus Variegated Chlorosis. It’s also fatal and has the potential to spread to North America via the shipment of infected trees. With a global economy and porous borders it’s bound to show up someday. Might as well get ready.

Gardening is a humbling lesson in evolutionary biology. It’s all about survival of the fittest. Work with evolution by selecting for immunity to pests and disease and you’ll harvest the rewards. Resistance is futile.

More info at piercesdisease.org.

If any of you readers know of a comprehensive list of resistant varieites for California please leave a link in the comments! So far I’ve been able to find lists for Florida and Texas.

Update 7/6/09: Reader Anduhrew sends an amazing link about a home remedy involving injecting antibiotics into an infected vine.

And here’s another article on possible cures.