<img src="http://latewire.com/images/fekken_random/cactus-xeriscape.gif">
Starting from Scratch :
Soil is the most important aspect of any urban agriculture setup. It's the soil that nourishes the crops, and so it's important to understand its composition. As mentioned in the previous section, geologically speaking, soil is composed of sand, silt, clay, organic matter, water, and air. For effective food production, the soil must have enough sand for drainage, enough silt (a sediment often originating from glacial erosion), clay, and organic matter for nutrition, and be sufficiently moist and loose for planting. In high-quality soil, all these components are balanced to create a highly desirable soil type known as "humus." [not to be confused with "hummus," though I've eaten at some restaurants that don't seem to acknowledge the difference]
The chemical makeup of soil varies greatly by region and site, and influences the growing characteristics of what's planted there. Three of the most important elements present in soil and their roles are :
- Nitrogen : helps green growth
- Phosphorus : helps fruiting, flowering, and root development
- Potassium : helps plants resist disease and drought
Together, these three elements are called "NPK," and their concentrations in a soil are a key part of assessing site suitability. Other elements are also vital ro plant growth. In the Southwest United States, soils tend to be lacking in phosphorus, manganese, boron, and zinc. Liberal application of high-quality compost and mulch will generally solve these problems, though there are element-specific amendments available (see note below).
Beginning to Plant
It's vital to consider your local climate when planning your urban ag adventure. Arizonans are lucky in that the planting season there is year-round. Check out this planting calendar put together by the Phoenix Permaculture Guild, especially if you live in an arid climate :
http://bit.ly/UIWwNRegional climates are generally discussed in terms of "climate zones." Each "zone" indicates a specific "hardiness" level that plants are recommended to have for planting in that zone. Most commercial seeds are clearly labeled with zone recommendations. The greater Phoenix area is "zone 9b," for example; this corresponds with a "low desert" climate. It's wise to choose plants that are known to thrive in your climate zone -- native plants or plants from seed that are marked as OK for your zone (one zone "higher" is generally OK -- for example, zones 9 and 10 are usually OK in Phoenix). Note, however, that seeds for which your climate is on the outer range (for Phoenix, that'd be like a seed packed labeled "Zones 3 to 9") are not a very safe bet. It's best to pick seeds for which your climate fall in a moderate range ("Zones 6 through 9").
<a href="http://latewire.com/images/fekken_random/climate-zone-map.JPG"><img src="http://latewire.com/images/fekken_random/climate-zone-map.JPG" width="800"></a>
Seeds and Transplants
Most seeds take 7 to 14 days to germinate, and then they have to sprout and grow. 60 to 90 days of growing are then needed before the plant will fruit. Transplants, on the other hand, are already germinated and sprouted.
Transplants are sometimes faster to grow, but there are factors you'll want to consider before opting for transplants : After transplantation, "buffer time" is needed for the plant to acclimate itself to its new environment, as each transplantation diminishes its resistance to drought, disease, and pests for a time until the plant recovers from the transplantation "shock". Accounting for this, leafy greens generally take about 30 days to grow after transplantation; fruiting plants, 90 days; and root crops, more than 90 days.
The bottom line is that it's generally better to grow from seed, where you'll control the entire plant life cycle. If you must start a plant indoors, try starting seed in a container of the same soil into which it'll be transplanted (the soil from your planting bed) in order to minimize the "shock" effect.
Notes on planting in November, December, January in Phoenix :
If you have seed packets that say "plant after danger of frost," that means winter planting in Phoenix. This is the time to plant what other people call "early spring vegetables." If you hear a warning of frost (rare, but it happens), just cover the plants with lightweight material (newspaper, old bedsheets, etc) by nightfall, preferably over a simple frame or stake. This will slow heat loss and prevent frostbite. Be sure to remove the cover in the morning.
Asparagus (note : must grow for one full year before you eat it), lettuce, broccoli, cauliflower, potatoes, and other traditional "spring" crops are ideal to plant at this time. Seed packet instructions indicating "warm" climate mean Arizona fall through spring -- not summer.
Potatoes and root crops are best grown in loose, well-drained soil; mulch can be added to the soil to improve drainage. For potatoes, cut up the seed potatoes into one-inch pieces (this small cutting encourages them to grow quickly) , place the seed potato cutting eye-up in a depression you've made in the soil, and cover with a mound of mulchy soil. Keep the mound well-watered. When the flowers begin to bloom, you can start "robbing" new potatoes (don't take too many at once or the plant will wig out).
Notes on planting in February and March in Phoenix :
February and March are the times to plant what other people call "summer crops." These include tomotoes, peppers, okra, eggplant, melons, squash, and similar items. These need to germinate in cool 70-to-80-degree conditions and flower before the temperature hits 90 degrees. Plant early to encourage strong root systems, because a summer harvest demands roots that will bring in plenty of water and nutrients to support the plant. Don't plant late! Leave the plants in after harvest to keep weeds away and promote soil health.
A note on soil amendments :
In order to get your leached, weak soil up to snuff for planting food, you'll need to supplement its composition with "amendments" -- that is, additives. Now, many people use chemical fertilizers and such to boost productivity, but not only is that approach expensive, but it can have grave effects on your soil health in the long run and plants in the short run. Chemical fertilizers, which generally contain a lot of potassium and nitrogen, can degrade your soil's quality by increasing its salinity and raising its pH to high levels of alkalinity (these factors are worst in arid climates), and can lead to "fertilizer burn" (the symptom of which is leaf tips turnign yellow), which damages crops.
Therefore, it's best to avoid these chemical amendments altogether and stick with quality compost that you know is free of chemical rubbish. Compost will feed the crops with a broad menu of needed elements, at concentrations that are healthful for both the plants and the soil. Plan your urban agriculture setup well and with a mind toward growing region-appropriate crops, avoid monocropping in favor of rotational and companion planting, and apply sufficient compost, and you should never require the use of man-made chemical amendments.
In addition to traditional compost and compost tea, a very effective natural soil amendment is work castings -- that is, worm poo. This high-powered yet safe soil amendment is available commercially; you can also get yourself a "vermiculture" setup or "worm farm" and grow your own.
There are several other "natural" amendments which are viable for urban agronomy in cases where available compost and worm castings prove insufficient. For nitrogen boost, alfalfa meal is available. For phosphorus addition, rock and colloidal phosphates (ideally added to nitrogen inputs like manure at the composting stage, but also possible to spread directly on the soil) are options; it's advisable to check to be sure that these haven't been processed in ways that might leave harsh residues.
A note on hanging gardens :
Hanging gardens are believed to have been prevalent in Babylonian and Sumerian societies. Those were some of the hippest desert civilizations of their time, so they must have been onto something. In hanging garden arrangements, the plants actually grow upside-down. Ideal candidates for this method are tomatoes, eggplants, and similar crops. Hanging gardens create shade, double your available space, cools the environs, and is generally efficient. Old or dead trees are ideal platforms for hanging gardens, but rebar structures, chicken coops, and big fences serve very well. Terra cotta pots with a hole in the bottom can function as hanging planters.
Part 4 coming soon
The bulk of this information is drawn from the lecture series "Designing A Vegetable Garden" as presented by Heather Welch at the Phoenix Permaculture Guild
<img src="http://latewire.com/images/fekken_random/cactus-xeriscape.gif">
Starting from Scratch :
Soil is the most important aspect of any urban agriculture setup. It's the soil that nourishes the crops, and so it's important to understand its composition. As mentioned in the previous section, geologically speaking, soil is composed of sand, silt, clay, organic matter, water, and air. For effective food production, the soil must have enough sand for drainage, enough silt (a sediment often originating from glacial erosion), clay, and organic matter for nutrition, and be sufficiently moist and loose for planting. In high-quality soil, all these components are balanced to create a highly desirable soil type known as "humus." [not to be confused with "hummus," though I've eaten at some restaurants that don't seem to acknowledge the difference]
The chemical makeup of soil varies greatly by region and site, and influences the growing characteristics of what's planted there. Three of the most important elements present in soil and their roles are :
- Nitrogen : helps green growth
- Phosphorus : helps fruiting, flowering, and root development
- Potassium : helps plants resist disease and drought
Together, these three elements are called "NPK," and their concentrations in a soil are a key part of assessing site suitability. Other elements are also vital ro plant growth. In the Southwest United States, soils tend to be lacking in phosphorus, manganese, boron, and zinc. Liberal application of high-quality compost and mulch will generally solve these problems, though there are element-specific amendments available (see note below).
Beginning to Plant
It's vital to consider your local climate when planning your urban ag adventure. Arizonans are lucky in that the planting season there is year-round. Check out this planting calendar put together by the Phoenix Permaculture Guild, especially if you live in an arid climate : http://bit.ly/UIWwN
Regional climates are generally discussed in terms of "climate zones." Each "zone" indicates a specific "hardiness" level that plants are recommended to have for planting in that zone. Most commercial seeds are clearly labeled with zone recommendations. The greater Phoenix area is "zone 9b," for example; this corresponds with a "low desert" climate. It's wise to choose plants that are known to thrive in your climate zone -- native plants or plants from seed that are marked as OK for your zone (one zone "higher" is generally OK -- for example, zones 9 and 10 are usually OK in Phoenix). Note, however, that seeds for which your climate is on the outer range (for Phoenix, that'd be like a seed packed labeled "Zones 3 to 9") are not a very safe bet. It's best to pick seeds for which your climate fall in a moderate range ("Zones 6 through 9").
<a href="http://latewire.com/images/fekken_random/climate-zone-map.JPG"><img src="http://latewire.com/images/fekken_random/climate-zone-map.JPG" width="800"></a>
Seeds and Transplants
Most seeds take 7 to 14 days to germinate, and then they have to sprout and grow. 60 to 90 days of growing are then needed before the plant will fruit. Transplants, on the other hand, are already germinated and sprouted.
Transplants are sometimes faster to grow, but there are factors you'll want to consider before opting for transplants : After transplantation, "buffer time" is needed for the plant to acclimate itself to its new environment, as each transplantation diminishes its resistance to drought, disease, and pests for a time until the plant recovers from the transplantation "shock". Accounting for this, leafy greens generally take about 30 days to grow after transplantation; fruiting plants, 90 days; and root crops, more than 90 days.
The bottom line is that it's generally better to grow from seed, where you'll control the entire plant life cycle. If you must start a plant indoors, try starting seed in a container of the same soil into which it'll be transplanted (the soil from your planting bed) in order to minimize the "shock" effect.
Notes on planting in November, December, January in Phoenix :
If you have seed packets that say "plant after danger of frost," that means winter planting in Phoenix. This is the time to plant what other people call "early spring vegetables." If you hear a warning of frost (rare, but it happens), just cover the plants with lightweight material (newspaper, old bedsheets, etc) by nightfall, preferably over a simple frame or stake. This will slow heat loss and prevent frostbite. Be sure to remove the cover in the morning.
Asparagus (note : must grow for one full year before you eat it), lettuce, broccoli, cauliflower, potatoes, and other traditional "spring" crops are ideal to plant at this time. Seed packet instructions indicating "warm" climate mean Arizona fall through spring -- not summer.
Potatoes and root crops are best grown in loose, well-drained soil; mulch can be added to the soil to improve drainage. For potatoes, cut up the seed potatoes into one-inch pieces (this small cutting encourages them to grow quickly) , place the seed potato cutting eye-up in a depression you've made in the soil, and cover with a mound of mulchy soil. Keep the mound well-watered. When the flowers begin to bloom, you can start "robbing" new potatoes (don't take too many at once or the plant will wig out).
Notes on planting in February and March in Phoenix :
February and March are the times to plant what other people call "summer crops." These include tomotoes, peppers, okra, eggplant, melons, squash, and similar items. These need to germinate in cool 70-to-80-degree conditions and flower before the temperature hits 90 degrees. Plant early to encourage strong root systems, because a summer harvest demands roots that will bring in plenty of water and nutrients to support the plant. Don't plant late! Leave the plants in after harvest to keep weeds away and promote soil health.
A note on soil amendments :
In order to get your leached, weak soil up to snuff for planting food, you'll need to supplement its composition with "amendments" -- that is, additives. Now, many people use chemical fertilizers and such to boost productivity, but not only is that approach expensive, but it can have grave effects on your soil health in the long run and plants in the short run. Chemical fertilizers, which generally contain a lot of potassium and nitrogen, can degrade your soil's quality by increasing its salinity and raising its pH to high levels of alkalinity (these factors are worst in arid climates), and can lead to "fertilizer burn" (the symptom of which is leaf tips turnign yellow), which damages crops.
Therefore, it's best to avoid these chemical amendments altogether and stick with quality compost that you know is free of chemical rubbish. Compost will feed the crops with a broad menu of needed elements, at concentrations that are healthful for both the plants and the soil. Plan your urban agriculture setup well and with a mind toward growing region-appropriate crops, avoid monocropping in favor of rotational and companion planting, and apply sufficient compost, and you should never require the use of man-made chemical amendments.
In addition to traditional compost and compost tea, a very effective natural soil amendment is work castings -- that is, worm poo. This high-powered yet safe soil amendment is available commercially; you can also get yourself a "vermiculture" setup or "worm farm" and grow your own.
There are several other "natural" amendments which are viable for urban agronomy in cases where available compost and worm castings prove insufficient. For nitrogen boost, alfalfa meal is available. For phosphorus addition, rock and colloidal phosphates (ideally added to nitrogen inputs like manure at the composting stage, but also possible to spread directly on the soil) are options; it's advisable to check to be sure that these haven't been processed in ways that might leave harsh residues.
A note on hanging gardens :
Hanging gardens are believed to have been prevalent in Babylonian and Sumerian societies. Those were some of the hippest desert civilizations of their time, so they must have been onto something. In hanging garden arrangements, the plants actually grow upside-down. Ideal candidates for this method are tomatoes, eggplants, and similar crops. Hanging gardens create shade, double your available space, cools the environs, and is generally efficient. Old or dead trees are ideal platforms for hanging gardens, but rebar structures, chicken coops, and big fences serve very well. Terra cotta pots with a hole in the bottom can function as hanging planters.
Part 4 coming soon
The bulk of this information is drawn from the lecture series "Designing A Vegetable Garden" as presented by Heather Welch at the Phoenix Permaculture Guild
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