Aley Chubeza #82, September 7th-9th 2011

Here Comes the Sun!

Autumn is just around the corner. Of course, it’s still hot and the sun is still ablaze, but its blaze is less scorching, and a cool wind wafts through at sunset to ease the heat of the day. The merge of summer and autumn creates this transitional season. The plants breathe small sighs of relief, the lettuce lift their heads, and the arugula, cilantro and dill dare to grow. The kale and tatsoi are taking their first baby steps in the field, wondering about the still-summery sun but placing great hope on autumn waiting in the wings.

Our planting schedule reflects this fusion of summer and autumn. Over the past two weeks we have seeded and planted corn, daikon, arugula, cilantro, dill, green beans, carrots, beets, turnips, peas, broccoli, cabbage, tatsoi and kale. Over the next two weeks they will be joined by mustard, spinach, cauliflower, fennel, kohlrabi, winter lettuce and garlic. The sweet potatoes now in the field, these last of the summer crop (or first crop of autumn, depending on your viewpoint) are fattening up underground. In a month we will begin checking on them to arrange hot orange “dates” with these sweet, healthy damsels.

At the end of this summer we made our first attempts at Soil solarization. Why heating the farmland to begin with? For the same reason we wash our hands with water and soap – to prevent the transfer of and infection from viruses, fungus and germs. Pathogens exist in the ground as well, and they stress and harm the plants. One of the most infamous is the fungus that caused the Irish potato blight of 1845, devastating the crops and bringing the greatest famine in Ireland’s history. Some one million people died of hunger, and a similar quantity emigrated to the U.S. Here at Chubeza, we meet soil borne diseases every year. Fortunately, they are not on a large scale, and of course, they do not cause disasters of Irish potato famine proportion. In any case, they must be carefully dealt with.

Soil solarization means taking a preemptive step. The idea is to clean the earth from pathogens before seeding, in order to prevent attacks on the plant. There are several methods to sanitize the earth. The first, developed at the end of the 19th century by German researchers, is to heat up the earth and disinfect it using steam. Subsequently, a chemical method was developed, where earth is cleansed by volatile chemicals, particularly the strong, familiar (and extremely toxic) methyl bromide. Chemical fumigation was very popular and common in large agricultural settings, where it seemed essential and irreplaceable.

But chemical soil fumigation is also very problematic, to say the least. The immediate problem is clear: these chemicals are extremely toxic to humans, animals, insects and earth. Unfortunately the disinfectants are not so picky about who and what they disinfect. They frequently hurt the beneficial natural enemies together with the pathogens, thus destroying the earth’s positive micro bacterial texture and violating the soil’s biological balance. The result is an ecological nuisance to the earth and environment. Upsetting the balance can be a double-edged sword: the moment the “good soldiers” are destroyed, the earth and plants no longer have any protection against diseases or pests which swoop in after the disinfection.

In 1976 an alternative method was developed by Professor Ya’akov Katan and his colleagues: disinfecting by heating the earth via solar rays. The idea is that the land will reach a sufficiently high temperature to kill disease-causing organisms and cleanse the earth of future problems. Weed seeds are also destroyed by the heat, which is why this method can be used successfully to rid an area loaded with weed seeds, and start off “on the right foot” with fewer potential weeds. The down side is that this is a powerful method, therefore somewhat violent towards earth insects. Sometimes positive organisms are hurt in the process, which is why we did not use this method in the past.

However, repeated fungus attacks on our garlic, onion and other crops made us rethink our decision. We also learned that our fear of injuring the biological micro bacterial texture of earth dwellers may be too high. Soil solarization research has shown that the temperatures reached by the earth (40-45 degrees Celsius) do not destroy all the pathogens and certainly do not kill the earth’s biological activity. Another development of the method, where compost is dug into the earth prior to the solarization, contributes to the increase of the microbial activity. So we decided to try it out.

How is soil solarization conducted?

  • Wait for the right season, i.e., summertime (July and August). Prepare the earth as you would prepare it for seeding and planting: clean remnants of previous plants, loosen the earth and add compost; form beds.
  • Water the earth with sprinklers. The wetness conducts the heat deeper and encourages biological activity. The earth should be saturated to a depth of 70 centimeters, using a lot of water. We had to run our sprinklers for 30(!) hours.
  • After the earth is sufficiently wet, cover it with a clear plastic sheet to heat it up.  This should be done very early in the morning, when there is no breeze and it is not too hot. You must be patient and exact. The sheet is pulled and stretched across the earth, and sealed by dirt along the sides to create a vacuum.
  • Then wait. It is recommended to keep the sheet cover over the earth for four to six weeks.

During this time, the earth heats up slightly more than the outside temperature, and strong gases accumulate on the vacuum under the cover. The result is a weakening of the pathogens, induction of “soil resistance”- basically bolstering the earth’s immune system. Unlike other disinfections, no “biological void” is created with soil solarization and there is no violation of the biological balance within earth. Of course, there is shock and a change from the previous condition. Instead, a different microbial deployment occurs in the earth, a one that is still rather balanced.

For those who wish to learn more about this fascinating subject, you can read more about it here.

In the saga of Chubeza’s soil solarization trial, there were several glitches along the way. After the first week we discovered that Noah, our good hearted but rambunctious dog, had decided to use the covered plot as his very own running course, and his footprints had neatly punctured the plastic along the beds… As despair enveloped the Chubeza team, we were given a vote of confidence by Moshe, our agricultural counselor, who encouraged us to seal the holes with earth and leave the plastic on for a few more weeks. Now it is ready to be removed. After we give the earth a bit of time to recuperate and let its positive microorganisms return to work, we will begin seeding and planting. We shall report our progress in the near future

For now, a good week to all, full of sun and breezes!

Alon, Bat Ami and the Chubeza team


What’s in This Week’s Season-in-Transition Boxes?

Monday: Basil or lemon verbena (Louisa), yard-long beans or cowpeas (lubia) or okra, corn, red peppers, butternut squash, tomatoes, cucumbers, onions, parsley or cilantro, scallions or leeks, pumpkin

In the large box, in addition: eggplant, cherry tomatoes, beets

Wednesday: mint (nana) or lemon verbena (Louisa), yard-long beans or cowpeas (lubia) or okra, red bell peppers, potatoes, butternut squash, tomatoes, cucumbers, onions, lettuce, leeks, pumpkin

In the large box, in addition: cilantro, cherry tomatoes, beets

And there’s more! You can add to your basket a wide, delectable range of additional products from fine small producers: granola and cookies, flour, sprouts, goat dairies, fruits, honey, crackers, probiotic foods and sesame butter too! You can learn more about each producer on the Chubeza website. The attached order form includes a detailed listing of the products and their cost. Fill it out, and send it back to us soon.



“When will you stop sending us pumpkin?!” asked Ariel, as we met last week at my daughter Shachar’s kindergarten. I sheepishly admitted that Chubeza’s pumpkin pile is indeed decreasing in height, but very slowly. It was then that I realized that you (at least some of you) may be in pumpkin- and- butternut-squash-distress.

Fear not! Here are several easy and delicious suggestions for using them well. (Feel free to interchange the orange vegetables in each recipe.)

Butternut Squash and Wild Rice Salad

Roasted pumpkin salad with honey and balsamic dressing

Pasta with roast pumpkin, feta & basil

Roast butternut pumpkin

Roast squash with coriander pesto

Squash, beans and coconuts curry

Pumpkin butter