AdAgrA 2015: Restoring the Waste Places

Breakout Session 5

Darren Greenfield

AdAgrA: Adventist Agriculture Association

2. Sweet Potato Production and the Adventist Advantage

So this is sulfate of potash, that's what we use.

When you get your soil test, you want to be aiming for the top end of the scale.

They have a range, they might recommend between 5 to 7 and a half percent of your CEC to be potassium, try to push it up to the 7 percent rather than staying down at the 5 because sweet potato like it, they'll use it all.

And then we feed an additional 2 to 250 pounds per acre through the drip system after they've been planted and it makes a difference, definitely makes a difference.

You see the thin small ones compared with the fat ones?

The thin ones are what they turn out like without the potassium and it can make a difference of double the yield if you feed the potassium.

So potassium is very, very expensive but it repays many times over if you use it.

Now if you leave the sweet potato in the ground long enough, they get big.

When you feed the potassium, they're short and fat.

And people, customers like them short and fat.

So if they're long and fat, they kind of, you know, not so, yes.

If the soil recommendations say it needs it, we put everything that the soil recommendation says.

And then in addition to that, well, the first 6 weeks is the vegetative growth stage, so we don't give it to them during that stage.

We give a little bit of nitrogen to them and a little bit of the kelp, and then once they've put on some nice tops, which they will have by 6 weeks' time.

Then we start feeding a little bit every week to them of the potassium sulphate through the rest of their life.

It's actually interesting that the majority of their growth happens in the last month.

A month before harvest you dig around and have a look at them and they're small and you start worrying that they're not going to get big enough but in that last month they just, they fatten up.

The other thing is giving them adequate water and it's going to vary depending on your soil type.

Let me just mention about the water and then I'll come to you.

The water, initially I followed recommendations from somebody who was growing them in an environment that got a bit of rain and the ground moisture content was higher and so I watered and he said, be careful, don't give them too much water and he told me how much to give them.

So the first year I did that and They ended up being longer and thinner because they go deeper to get the moisture, whereas if you give them enough moisture, they don't have to go as deep and they'll be shorter and fatter.

But you don't want them to be too saturated with water.

There's other issues that come from that as well.

They won't actually get big if they have too much water, so you've got to have the right moisture.

I guess Technically it is, but it's a natural, it's OMRI listed, it's not harmful, it's not in a toxic level.

The product that we use comes from Utah, from the Salt Lakes somewhere there.

Yes, you can get it in a, for broadcasting you wanna get a granular, they call it standard fines, it's like sand, and it broadcasts nicely from a spreader.

For the drip tape you can get the, what do they call it, ultrafine or something like that and it's solution grade and it's a white powder, it's very, very small particle size.

So weeding is the next thing you're going to deal with.

I'll tell you what we do, and you're going to have to adapt to your soil type, but we have heavy clay soil, and if you have heavy clay soil it holds the moisture a lot longer.

And so we give them about 3 hours on the drip tape.

Now, it depends on the spacing and rating of your drip tape and your supply line, if it's giving volume and so forth.

You want to be continually monitoring and feeling the moisture and making sure they're getting adequate moisture.

We do about a three-hour watering 3 times a week.

And we use drip tape that has eight-inch spacing.

Now if you use drip tape that has 12-inch spacing, you probably need to do about 4 and a half hours in our clay type of soil.

If you're in sandy soil, in Livingston, California, where it's the sweet potato capital, it almost looks like beach sand.

They give their sweet potatoes 6 hours a day, every day, because it just goes straight through.

So just make sure that it doesn't dry out and it stays moist enough that they're not going to go deep looking for water.

First year you're going to experiment and you'll learn from it.

So you might make some mistakes the first year, but they're very, very hardy plants.

You can give them, you know I told you that the first water is the most important water they get.

If you didn't water them for the rest of the summer, they will stay alive and they'll grow a little bit and you might even think that they're going to produce something.

You'd probably dig them up and there might not be hardly anything there.

They're not going to show you by their leaves that they need water.

Most other plants will start wilting and drooping.

They have to be almost completely dried out before the leaves start looking like they're drooping.

So don't use the foliage as an indicator of water needs.

This little, we first started, everything was hand weeded.

This mechanical weeder just uses some shovels on a tool bar and goes in between the rows.

And if the ground is flat enough, it works really well because you can get the dirt piling up on top.

Then after our students were grumbling and complaining about having to bend over and weed, 1 of them said, come on, let's make a thing we can lie down on and weed.

And finally he twisted my arm because I got tired of the complaining.

And so we basically modified the transplanter so that they could lie down and weed.

And it actually increased our efficiency from what used to take us 2 weeks by hand, we got done in about 3 days.

And they were much happier because they were...

The thing with young people is they don't like to be more than a hand reach apart from each other.

And so when they're in their rows, some of them are faster than others, but the fast ones they wait for the slow ones because they don't want to be separated.

So you slow the whole process down to the slowest 1, whereas with this, the tractor sets the pace.

They all work at the same speed, and they're chatting away, and they've got a weeder in both hands, and it's much better.

So you can see on this particular terrace there, you can see in front of the tractor the weeds are quite thick.

We try to get to them before they get to this stage, but even if they get to this stage you can go along and you can see behind there the weeds have been knocked back.

Once the sweet potato put on their vines, they basically smother the weeds down.

There'll be a few weeds that'll grow through, but we'll walk through and just pull the tall ones out and try to stop them from growing and getting to seed.

We go through and thoroughly weed them and it actually looks really beautiful when you've got all that green, especially in brown California.

Typically, this last year we did 3 and it was smaller for various reasons why we didn't grow as much.

But We've got contour, which is a little bit challenging.

In fact, once you get beyond just a gentle slope, the amount of labor involved is probably nearly 4 times as much.

So if you're trying to grow on a hill, a lot of it's manual.

You eliminate the tractor for some of the processes.

We get our elementary kids involved and try to include them in whatever they can contribute.

So we first remove the drip tape and I've tried several different harvest methods and because of our soil, we have a lot of stones in our soil and we have a variation of moisture content.

So this tool that you can see there, it's actually a drip tape lifter.

I just mounted that on a toolbar as well.

And it goes underneath and pushes them up to the surface.

And then you just grab the vines and pick them up and separate them.

You have some coulters in front and a coulter, if you don't know what a coulter is, the kids call it a pizza cutter.

It's just a giant wheel, you know, I think it's 26 inches, the 1 that we use.

Ric España

Alan Seiler

Irrigation

My name is Rick Espana and I am the farm manager at Eden Valley Farm and my buddy here.

I'm Alan Seiler and I know some of you from the last class, but I'm from South Central Oklahoma with Better Together Farm.

And we both met at Bountiful Blessings Farm.

And it's just amazing to see how God has led our lives since then.

We will be going over irrigation systems, and I'm just gonna give you an overview of what we're going to be discussing.

First, we're going to deal with water source, and Alan is going to be presenting that, where our water comes from and what it's like.

Then we're going to go to what we call the pump house and the components of that.

Then There is the main water line and then I'll be dealing with the pump house, Alan will be dealing with the main water line.

And then we will have what we call the valve box.

The valve box is basically distributing the water to where you want the water.

And then the last part is going to be the types of systems once your water is out where you need it.

And then at the end we're going to have a time period for questions and answers.

All right, so Alan will be dealing with the water source.

Okay, so how many of you here are wanting to do this as a home garden?

Okay, and how many are wanting to do it, is there anyone here that wants to do it as far as a production system?

Okay, so when we're looking at water sources, there's a few things that we need to consider.

There are many different types of water sources that you can have.

So, for instance, this could be a well water.

This could be you are buying water off of a local water co-op, which then it comes pressurized automatically from their pump stations.

And so part of the pumping system is not necessary.

It could be coming from a gravity-fed stream that's up higher than you or a spring, or you could be like people in Washington and places like in the San Juan, Keene Valley, where they're pulling out of aquifers, sorry, not aquifers, they're pulling out of aqueducts and stuff like that.

Either it runs along the ridges of the mountain and flows down, or it runs along the side of their fields and they pump out of it.

1 thing to take in consideration, if you are going to be doing anything beyond a residential situation, you really want to make sure what your water rights are for the particular land that you're looking at or that you even have currently.

So how do you find out what your water rights are?

But 1 of the good things to do is get in touch with your local water resource board.

Oklahoma, where I'm from, has, it's called the Oklahoma Water Board, and they can be found online.

And basically these people, they graph the aquifers in your area, they know about the surface water, ground water.

In Colorado, actually you can't even harvest water off your house, because the water is the domain of the public and so you even catching water off of your house is considered a I'm not sure if it's a felony or whatever type of situation but anyways it's not your right so you want to make sure wherever you're coming from that you actually have the right to the water that you're using and the quantities that you need it.

Another thing to think about is that how much water do I actually need?

If you're growing things like cactus, it's going to be a lot different than you're growing things like pecans or versus vegetable production, which is what we do.

If you're doing vegetable production, the rule of thumb is about 15 gallons a minute per acre of land that you're growing, okay?

So 15 gallons a minute per acre of land that you're growing.

And another thing to consider, so for instance if you're looking at a well or something, it's like, oh it has a good well on the property, well does it really have a good well?

Can it actually give you a minimum of 15 gallons a minute?

Some wells give beyond that, but you just want to know what your restrictions are because when it comes to water sourcing, that might mean you have to put in some sort of reservoir to capture that water overnight and then pump out of that reservoir during the day because you don't want to bleed your well dry and so on and so forth.

Another thing to think about, and this kind of gets into the pump house situation, but what PSI do I want this water at?

Most of these irrigation systems that we're gonna be looking at today here, like drip tape, which is this kind of stuff, we'll talk more about them, or micro sprinklers or stuff like that have a wide variation in the PSI that they need to actually run the system at their optimum performance.

Systems like this, whether it's overhead irrigation or on ground overhead irrigation like these wobblers and such, they require at least 30 to 40 PSI to run those systems at their optimal level.

So you want to think when you're looking at a water source, I want at least 15 gallons a minute and I want to operate my system at the max.

It's not always possible to get it higher.

So we recommend, or at least I recommend, and I think Rick would concur with me, is that you're looking at about 30 to 40 PSI in your system to be able to meet the needs of these variable overhead and systems that need these higher pressures.

That's about it for water source because there's a lot of variations.

We could go into details, but that's a good overview to get you started.

1 thing about if you're running off of wells, you have to take into consideration what water you need for domestic use.

So it's not just irrigation, but what you need for both domestic and irrigation.

And also to take into consideration what is the flow at the driest time of the year, in case your water table really goes down.

Yeah, and so when I say 15 gallons a minute, that means 15 gallons a minute at least all year round, okay?

If you put up, I don't know where you're from, are you from here in Texas?

Okay, so it would be probably the Oklahoma Water Texas Board or the something like that.

So the trouble with the irrigation system class is that there's such a wide variety of water sources and needs It's hard to cover it all in just 1 hour.

So our water source, whatever it is, is coming in to what we call a pump house.

And there are different components in this pump house.

Most of the time, your well will have a pump.

If you're on city water, that's already got pressure.

But there's some cases where you actually need to boost up the pressure.

So in my condition In Colorado, we are getting water 100% from a canal.

And so we bring that to a pump, and then we put a pump on that and boost up the pressure.

1 of the most important things that you need in this setup here is your filter.

Filtration is very, very important because the systems you use out in the field can easily get clogged by small, small debris.

You want to put on here a pressure regulator, not a regulator, but a pressure gauge.

It just tells you how much pressure you're actually getting.

It's actually about Rick when we were at the farm.

He was drinking out of the water hose and it was kind of clogged with something.

They don't have a very good filtration system.

Clean it up and He screws off the cap of the thing to look at it and there's a little salamand in the top of the thing, so you want to make sure you have good filtration.

I didn't know at that point that we were getting water straight from the pond.

So the pressure gauge lets you know what's going on with your water.

If your pump is pumping, whether underground at the well or above ground here, your pressure gauge tells you if your pump is functioning appropriately or if there's some debris in your filter that's reducing the pressure.

I'm always watching my pressure gauge to see, because I have so many components running.

And so sometimes it's the pump, sometimes it's the filter.

Would you suggest putting a pressure gauge before and after the filter?

I actually have several pressure gauges in different areas because I have water coming and I have extra filters in addition to my main filter.

So there are different types of filters and different qualities.

Yes, here's 1 that's got a screen, a fine mesh screen for trapping debris.

1. Sweet Potato Production and the Adventist Advantage

So, sweet potato production and the Adventist advantage.

When we think about the Adventist advantage, we think of the health message.

If you were to Google Adventist advantage, you would come up with a bunch of articles about the longevity of Adventists and the health principles and so forth.

And you're probably wondering, well what does that have to do with sweet potatoes?

Well, you will find out as we get into it.

But as we grow and promote sweet potatoes, we're actually, it's part of promoting the health message.

And it goes really hand in hand and it provides excellent witnessing opportunities and the ability to help people many of whom are struggling with health issues.

Sweet potatoes, let's talk about the properties of them a little bit.

Sweet potatoes, by some authorities, many of them, are rated as the best vegetable that you can eat.

They're loaded with carotenoids, vitamin C, potassium, and fiber, and many other minerals and beneficial elements.

The skin has as much antioxidants as blueberries and 3 times the nutrients of the flesh.

So don't peel your sweet potatoes, buy organic ones that have not been sprayed with a fungicide.

The conventionally grown ones, you can go on and watch on YouTube how they pack them in the packing sheds.

Just before they drop into the box, they are sprayed with a fungicide to give them a longer shelf life.

I don't know how good that is for you but I would prefer not to be consuming that.

The sweet potato can absorb up to 62 minerals if they're present in the soil and that's more than 3 times most produce that we eat.

They're so good that NASA sends Sweet Potato with their astronauts up into space because they know it's going to provide them with nutrition.

Sweet potatoes have an anti-cancer protein called sporomin.

It's 80% of its total protein and it's so powerful against cancer that a person with tongue cancer that eats regularly the sweet potato, it's like a chemo treatment on the cancer that the cancer will actually go into remission from just eating the sweet potato.

Studies have been done, if you wanna learn more about that, If you go to nutritionfacts.org, Dr.

And more than just tongue cancer, actually the protein can be absorbed into our blood and apparently there's studies out there that are quite amazing as far as what it can do.

The leaves, if you grow them, you can eat the leaves.

And I'll just read to you what I read in this particular article.

It was a posting on Facebook, but it did have a reference to a PubMed study, and I went there and read a lot of the language was over my head, but this is what the posting said.

Sweet potato leaves kill 94% of prostate cancer cells in vitro.

An extract of sweet potato leaves was discovered to be extremely toxic to prostate cancer cells in a study killing 94% of them and slowing the growth of prostate tumors in mice by 75%.

Other research has shown that these super greens are also active against breast cancer, lung cancer, colon cancer, stomach cancer, and leukemia.

And the health benefits of these greens are not just for the lab.

1 study out of Taiwan showed that eating at least 100 grams per week of this super vegetable decreased lung cancer risk by up to 57%.

In other studies, sweet potato leaves boosted immunity in humans and lowered blood sugar in mice with type 2 diabetes.

And if you need an energy boost, sweet potato leaf could be just the vegetable for you.

A recent study showed it significantly relieved fatigue in mice, increased exercise capacity, and even boosted muscle glycogen levels.

They are an excellent source of potent antioxidants called polyphenols, including the unique and powerful, not sure if I can pronounce that word, but you can read it.

And alkaline diet fans, take note, these greens are 1 of the most alkalizing vegetables out there, delivering 400% the alkalizing power of pure lemon juice ounce for ounce.

So maybe instead of wheatgrass we should be out there juicing sweet potato leaves.

So I come from Wima Institute where we have the college and the Academy and it is a really good fit for us with a school program that is totally out of sync with our growing season.

So we plant in May and then through the summertime we just water and weed, keep them growing, and when school comes back into session again, then we harvest.

We could possibly start in September, but giving them more time is beneficial to getting them to a larger size.

We store them, we wash, pack, and ship them during the winter, and we use student labor for that.

It provides excellent work experience for unskilled students.

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All Teachings

2. Sweet Potato Production and the Adventist Advantage

29m

Irrigation

58m

1. Sweet Potato Production and the Adventist Advantage

32m

2. Online Marketing: The Next Step

1h

Tree Grafting

1h

2- From Seed to Harvest: Planning and Scheduling to Maximize Yield

1h 12m

Growing When You Can’t Buy or Sell

1h 23m

Container/Suburban Gardening

1h

Intro to Small Fruit

58m

1. Online Marketing: The Next Step

57m

The Ideal Soil: Carbon Fertility

55m

Irrigation Management

57m

Sound Doctrine