Comments needed on a vegetable garden plan

I am planning a sheet mulched vegetable garden, for both perennials and annuals. For irrigation, I was thinking of using slightly off contour Swales. My soil is Nunn loam, with about 23 percent clay, 39 percent sand, and 37 percent silt. I would be moving nutrient rich water from a duck pond once or twice a week into the swales. I envision the swale looping back and forth across the slope, ending up in a level infiltration swale to soak up excess water. There would be mulch in the bottom the swale. The berms would be used as paths.

My questions are; is this a good plan? And, how quickly will the water sink into the soil? I imagine that if I lay the swales at too much of a slant, all the water will end up at the bottom; if little, all the water will end up at the top. But I suppose that given this soil composition, there would be an optimal angle.

Hi Gilbert

Do you have a scale drawing of this plan that you could upload? I think that would help people visualize the size of the property and the way in which you envision laying the system out.

For example the wording of "swales looping back and forth along the slope" makes me think you are connecting them, as opposed to having them on contour and having a spillway that feeds the next level of swale? Or maybe it's an issue of semantics and this is more of an "irrigation ditch" as opposed to a swale (which Geoff Lawton defines as a "tree growing system on contour")... Swales typically have level bottoms as opposed to slanted.

Things we would need to know is how much slope you have, where the pond is located (assuming at the top of the slope if it is to be drained down to the gardens), what volume of water is in the pond, how much garden space you're draining it to and how frequently.

Someone who has similar soil to you would have to speak to this - but I think with almost 40% sand, you might not get irrigation all the way to the bottom of the slope - it might drain too quickly. But that is dependent upon how much water is in the pond and how much garden you are watering and how much slope you have.

As for "optimal" anything - Keep in mind that most systems are "rough" at first (except if you are VERY experienced) - I would very much doubt if there was a person on this board who has not at least tweaked a system, more than once. I've actually overhauled whole areas more than once to fine tune it. This is just me getting experience through observation - nothing wrong with it. But you should expect to do some tinkering with any system you put in, especially when new.

Hello Jennifer,

Unfortunately, I don't have a scale plan. Google earth (I am not sure how much this can be trusted) tells me that the land loses two feet of height in 30 feet of distance. In this case, my visual observation leads me to believe that Google Earth is about right. I will be building a bunyip water level soon to test it.

The plot is backyard scale; about fifty feet long, varying from thirty to twenty feet across.

Yes, I was thinking of leading the water along a gently sloping path across the slope, ending up (in its last course) as a level infiltration swale. I can't lay the swales parallel to the slope at the top— too close to the house. So this is an irrigation ditch. I think Brad Lancaster would call it a Diversion Swale. In his terminology, it will lead to an infiltration basin at the bottom of the hill. A 1860s historical museum nearby uses trenches like this in their garden, but they have them going straight down an (almost non-existant) slope. I think that I could get serious erosion on my site if I tried that. The pond is not directly at the top of the slope, but I have a way to lead the water there. If I was not trying to use duck pond water, I would not be doing this. I am also hoping that any chlorine in the water will evaporate off the pond before it ends up in the garden. I would be releasing about 560 gallons of water into the head of this swale once a week.

And yes, I realize that I will certainly have to tinker with it. I am sure I will make mistakes; but I would like to hear about other people's mistakes, so that I can make new and better mistakes. (Dave Jacke.)

Gilbert Fritz wrote:I am sure I will make mistakes; but I would like to hear about other people's mistakes, so that I can make new and better mistakes. (Dave Jacke.)

LOL - ah yes, the quest for "new and better mistakes" - I know it well!! It will be exciting to see what you come up with. I've come up with some real doozies in my time!! Friends of mine who have loads of permie cred (certified water harvesters - trained by Brad himself, certified permaculture designer, watershed steward, master gardener....yadda yadda) - we compete to see how many times we change our minds about things and do "do overs". We've come up with some basic rules like "if a plant can't survive being moved three times, it's not worth having". Or, "if it needs water after three days of 115 degree heat - it's not worth having (on the 4th day - it makes the 'ok' plant list)". The list is fairly extensive!

This sounds like a good place to start. As has been said, you will have to observe and interact as needed. Swales or not terminology doesn't matter if it works. I would try to avoid too much slope in your beds, maybe try going on contour with crossing pipes instead of sills to save growing space.
My main concern is where would the chlorine be coming from??? Are you draining a swimming pool into your duck pond? Or is it just chlorinated city water that you fill the duck pond with? Either seems less than ideal. Can you catch rain water or anything else? I wouldn't want to drink that stuff, I'm sure the ducks would rather not.

Unfortunately, Rain and Grey water are both currently illegal in Colorado. But I will be designing the system with both grey water treatment and ran water collection in mind, but using city water at first. This way I can test out my systems with no risk ( I would rather have earthworks designed to hold greywater fail to do so when there isn't actually any greywater in them) and be ready for a change in the laws (which I think is coming.) People CAN drink it and survive. So it should be OK (though far from ideal) in the garden.

Gilbert Fritz wrote:Unfortunately, Rain and Grey water are both currently illegal in Colorado.

Illegal in Utah too, except a measly 100 gallon rain barrel...but...it is perfectly legal to protect your property by diverting rainwater away from your structures to elsewhere on your property to someplace convenient for managing that threat. Conveniently the convenient place could be the garden.

I've been farming on one level of another since 1984.

In these many years I have learned only 4 INDISPENSABLE rules:

1: It is always easier (in the long run) to overwater a garden than it is to underwater a garden.

2: Always have a drainage plan.

3: Location, location, location! Know your location, soil, water (crunch numbers: Most always ends up more than is needed) and basic weather patterns (prevailing winds/rain-timing and volume/temp) for your area.

4: Create/exploit micro climates(shade/airflow/water flow, etc).

Without knowing more (temp zone / surrounding environs / possible crops / hours per week applied / ave monthly rain fall / physical location of land / weather patterns / possible resources / etc), most information will be postulation/guessing....

Whats the zip code?

A little more info would be helpful

We are in the Denver Metro, with a zone five (recently, more like zone six) climate. Crops would be the typical vegetable garden stuff, tomatoes, squash, potatoes, brassicas, but not salad greens, which will be grown in a Biointensive bed and hand sprinkler watered. Rainfall is low, but can come in huge bursts in summer thunderstorms. The yearly average is 14 inches, but it can be much higher or lower. The plot is in the upper levels of the Platte River valley, above any possible flooding by a long way. The land is prime farmland if irrigated. Currently a patchy lawn. Will be sheet mulched.

Peter Smith wrote: My main concern is where would the chlorine be coming from??? Are you draining a swimming pool into your duck pond? Or is it just chlorinated city water that you fill the duck pond with? Either seems less than ideal. Can you catch rain water or anything else? I wouldn't want to drink that stuff, I'm sure the ducks would rather not.

I'm assuming you're using city water that has a certain level of chlorine? Usually chlorine will evaporate off of a body of water like a pond (this is why you have to keep adding chlorine to a swimming pool), it will do so faster if there is aeration of some kind - even ducks frolicking in it.

My two bits:

In general, as long as you have a retention pond that has at least 96 hrs of settling time, don't sweat the chlorine. The environs should take care of most of it and if you feel iffie about it, plant a buffer zone of crops that you would't mind losing.

No crop failures, only learning experiences.

Sounds like the swales and such will work fine.

***Better than even chance your local Extension Office will have a laser level or survey transit (if not, your county commissioner/road commissioner should have one) . Never hurts to ask. They'll also have some planting guides (which make pretty good tinder when you don't have a rocket stove) which may prove to be helpful. Your tax dollars have paid for it. Ask to use it!

Maximize biomass production with overplanting:

Mixed lettuce works well for me, though I lose 75%. The shade slows/halts "weed" growth and I still get some food and LOTS of biomass which: retains moisture, retains existing soil, builds soil and attracts polinators.

Use existing nutrition in soil:

Lots of root crops. I only harvest 1/3 of what I plant. The remaining produce, while rotting, is bringing nutrients from deep soil and depositing them in shallower soil, which future plants can capitalize on.

More to come upon request.

Hello Chris,

If you have more advice, I will be glad to have it.

A long time ago I started planting lettuce seeds really densely. And it seems to work; I think they like it. I have done that in both Pennsylvania and in Colorado, and it worked fine in both places. In Colorado, I spread a bit of landscape fabric over the bed till they started germinating.

So I will be doing a small biointensive bed, overhead watered every day, for baby lettuce and other mixed greens. All the other veggies will go in the sheet mulched, swaled garden.

Concerning wind and sun exposure:

I use vertical crops (corn/sunflowers/milo) to provide wind break and control sun exposure for less tolerant plants.

Those crops will compete for nutrients and water, so some experimentation would be advisable.

"Biointensive" is kinna vague.

While such a growing strategy can be productive, whats the cost difference between "biointensive" and field farming?

I don't generally measure cost in USD/FRN. I wondering about manpower and infrastructure.

Hello Chris,

As far as biointensive goes; there is no infrastructure. There is a lot of work, but it produces a very high yields per square foot (and per hour.) It is most useful when high yields must be obtained with few inputs on a small space. (There is no importing of organic matter; four thousand square feet produces all the food for one person, as well as the compost and seeds to continue the garden.)

I will have a few small biointensive beds in zone one for greens. But I will be using sheet mulch for the main garden (zone two.)

Sounds like you really have a good bead on things to me

Plan on any experimental crop beds?

Yes, I am planing all sorts of experiments, both with plants and methods.

As for plants, every perennial vegetable I can lay my hands on. (And some tropic ones to see if they work as die-back perennials with a good mulch. Denver soils don't really freeze much, especially in a good micro climate. We are zone five; but only for a few nights a year. Most winter days, the lows are in the twenties, and the highs are in the fifties.) I will also be trying out lots of heirloom tomatoes (I found out last year that black tomatoes do much better than red here) and various bean species other that P. vulgarus.

As for methods, different pruning styles, perhaps a small waffle garden, and some electromagnetic experiments.