Purple Sweet Potato Descriptions and Summary of 2013 Harvest

After growing 3 different purple sweet potato varieties this year, plus an experimental stint with a Stokes Purple sweet potato, I am happy to give a description of each of the purple sweet potato varieties I have grown, along with their growing characteristics.
 

My son finding an orange sweet potato

Taste Testing to inform descriptions - My children exhibit a lot of potential in taking pictures

All Purple: Long roots are often produced in locations of excess water with tubers often developing deep in the ground. Good yields of mildly sweet potatoes with a consistently purple flesh.

Alabama Purple or Purple Delight: Mostly top setting tubers of variable shape and size. Heavy yields of smooth textured savory tubers with purple flesh.

Dingess Purple: Top setting tubers of very marketable shape and size. Moderate yields of tubers with a rich, complex flavor and dark purple flesh.

Currently, if you live in Tucson and would like to buy any of these sweet potatoes you can contact me through this Craig'slist post. All proceeds go to my garden.

I grew a Stokes Purple Sweet Potato (starting in August or September)

In summary – I would have to say that the Purple Dingess are my all-time favorite, despite the meager 15 pound yield. Harvesting and working with the Dingess Purple Potatoes was much easier than working with the All-Purple or Purple Delight tubers. It would be well worth it to try to cross Dingess purple with another purple variety, such as Alabama, to seek to increase yield.

My Sweet Potato vines in November

Sweet Potato Vines have problems staying on my property

The final results of my 2013 harvest are 165 pounds of mostly purple sweet potatoes from my 7’ by 15’ summer garden bed, meaning the garden produced more than 1 pound of sweet potatoes per square foot, in addition to everything else produced this last summer. That being said, in the long term I am really seeking for quality over quantity. I would much rather have a tasty Delicata squash over a big poor-tasting squash. I am very grateful for such a good harvest, though I will definitely be changing some things this next year. Two of the things I will be changing for next year include planting my slips later in May and applying more EM-1 throughout the season to see how it affects my sweet potato vines.

Purple Sweet Potatoes make great pie.

EM-1: My experience with EM-1 was that it did nothing for any of my garden plants – including the legumes. The exception to this was with my sweet potatoes. EM-1 greatly increased my sweet potato yields. I highly recommend using EM-1 as an inoculant for sweet potato slips to increase yields. It is worth every penny if you are really into growing sweet potatoes. I diluted my EM-1 in purified non-chlorinated water and sprayed it on my young plants until the ground was soaked. The results in both vine and root growth were impressive. In fact, I would warn gardeners that the growth of EM-inoculated sweet potato vines is so vigorous that, in crowded conditions they will grow several feet off the ground.

EM-1 dramatically improves sweet potato growth

I am currently doing some research on culturing my own shelf-stable EM with the same characteristics as the EM-1 that I currently use. I will gladly share any success I experience from my own experience brewing activated EM - as I have time to do so. Another interesting thing is that, from some of the research I found, the Anthocyanins contained in Purple sweet potatoes can better retain their health benefits and color in storage with the presence of lactic acid (7%), which happens to be one of the ingredients in EM-1.

2013 All Purple Harvest

In early April, when Tucson’s average high temperature rose above 80 degrees, I put out my All Purple Sweet Potatoes to start growing slips.

 

A few All Purple Slips I transplanted though I will probably not transplant next year.

 

With some EM-1 my slips really took off by mid-may

 

 

Slips can take a long time to start – especially if being grown indoors. That is why I have been working on a new way to start my slips outdoors. Though I have greatly improved my method for growing sweet potato slips, I believe that my sweet potatoes do much better when I wait until May 1^st to start growing out slips.



 

My second harvest of sweet potatoes required a flashlight to procure

 

When the time finally came to harvest my All Purple sweet potatoes from the garden, I had to do so a little at a time. It is difficult to harvest a sweet potato that can mature over a foot below the ground, and doing so requires loose soil and some dedicated time to feel through the soil by hand.

 

 

Some of my first harvest of All-Purple Sweet Potatoes

 

 

Some of my second All-Purple Sweet Potato Harvest

 

 

One of my larger All-Purple Sweet Potatoes

 

 

Another large All-Purple Sweet Potato.

 

 

By the end of my harvest I felt both good and bad. It seems that the quality of this variety of sweet potatoes decreased from going into the ground so early. A few of the larger sweet potatoes did not exhibit the color or texture I would have expected from this variety. On the other hand the harvest of 95 pounds was a nice way to finish my summer garden harvest.



Some of my second All Purple Sweet Potato Harvest. Can you find the nickle?

Gardening When it Counts by Steve Solomon

Should you want to be a self sufficient gardener and you have some time on your hands, I would highly recommend picking up a copy of Gardening When it Counts by Steve Solomon. This book does a good job overviewing many of the techniques required to be able to live off the land, as long as your climate produces a moderate amount of rainfall. Though I do not agree with everything Steve Solomon says, I feel that he has very helpful thoughts on various subjects of gardening and the general ideas in his book are good.

A Definite Good Read, but filled with opinions

The general premise of Solomon’s book is that there may be a time in the future in which Gardeners are faced with an inadequate source of irrigated water and/or fertilizer but will most likely have access to seed and land. One of the chapters that covers this subject, entitled “Watering… and Not” includes a very helpful table with plant spacing (based on average rainfall) and plenty of helpful ideas when planning out growing vegetables with minimal water.

Along the same lines, another chapter entitled “What to Grow and How to Grow It” contains pictures of roots on a 1 foot grid from Weaver’s Root Development of Vegetable Crops. These root pictures are very helpful to gardeners because they show how to grow crops based on how their roots grow and the amount of space each root system requires. The “What to Grow” chapter also included some very helpful hints on growing, including what to expect from specific vegetable varieties and some information on inbreeding depression.

To refute a point Solomon makes about seed companies - my lettuce (lower right) is very strong viable
 seed from SESE while my beets (top right and barely visable) seem to be growing poorly from seed sold
by Territorial. Both packets were planted the first season after receiving seed packets and the beets received
 more sun. The germination of the beets was poor and I will have to work on this beet variety to keep it going.
Territorial has sold me some high quality seed in the past. I use this illustration only to make my point.

There is a chapter that highlights making a good balance of nutrients in the soil and another chapter that highlights the use of raised beds based on berms rather than on borders. There is a chapter about seeds and growing seed as well as a chapter about composting.

Overall, if you have read and enjoyed any of Carol Deppe’s books or are interested in some basic fundamentals of sound gardening – then this is the book for you. Even though I did not agree with a few of the things Solomon wrote (raised rather than lowered gardens for dry climates and his negative views on Southern Exposure Seed Exchange) I would have to say that the book had some good ideas that were based on years of experience in a couple climates.

Update: I just found you can access an ebook edition that has some of the pages - if you would like to preview it before you dedicate any finances to this text.

The Dingess Purple Sweet Potato

Two Slips survived to make some beautiful sweet potatoes

Dingess Purple Sweet Potatoes were probably one of my favorite sweet potatoes to harvest this year. This was not only because the plant exhibited vigorous growing vines to begin with, but because the harvest is of marketable size and shape. Unlike the All Purple, which may root a foot under the surface, this variety tends to root near the top in more round tubers - making harvest much easier.

The younger slips and vines of the Dingess Purple can be hairy in appearance.

I would like to say that Dingess Purple will be one of my main varieties for next year, but I still need to do a taste test and rate each of my varieties accordingly. Though there is some anecdotal information about the taste of this variety on Tomatoville, there is nothing like doing a taste comparison to determine what variety will work best for the long-run.

My Dingess Purple Crop just as it came out of the ground.

After harvesting the first Dingess Purple potatoes, I became concerned that the interior may not contain a dark enough flesh. To determine the general color of this variety I cut a cross section of a smaller potato to see how it looked.



Dingess Purple Color looks good.





A long Dingess Purple Sweet Potato

  

 



A decent-looking Dingess Purple Sweet Potato



 

 

Though the harvest was not as much as it could have been (compared with the Purple Delight), it was over 15 pounds. Dingess Purple does an incredible job producing sweet potatoes that are just the right size for the market. As long as the flesh of this variety exhibits good taste and texture I will be growing this variety for many years to come.

   

The Dingess Purple Vines produced mostly marketable Sweet Potatoes

Purple Delight Sweet Potato Harvest

Before I was even finished harvesting last year’s sweet potato crop, I began to plan out how to trial my sweet potato varieties for this year. The delay between placing my order in November and receiving the sweet potatoes in a battered priority shipping box in May provided me time to think about how I could prepare to have a better harvest this year.

 

My poor-looking Purple Delight Slips

The battered priority mailbox that contained my sweet potato slips

My first encounter with the sad-looking slips I received in mid-May left me wondering if they would make it a week, let alone a season, in my garden. Having seen a slight improvement in the growth of my All-Purple Sweet potatoes in April with the application of EM-1, I decided to add some EM-1 to the plot. As the slips finally established themselves I honestly expected very little but still held out hope for the best.

My Purple Delight sweet potato slips (to the left of the bush bean)

The harvest of root crops can be both exciting and scary - in that the gardener has no idea what good (or bad) could possibly lie just under the surface of the soil. The longer the span of time the crop requires to mature, the longer the gardener is left to imagine how the tubers are growing, with only the top of the plant to give any clues to the health of what lies below. Revealing what lies under the ground is like unwrapping a large gift, not knowing beforehand if it contains something really wonderful or something you would rather give away.

The area that the Purple Delight covered is in the foreground

The Purple Delight Vines take up roughly 1/5 of the area on the bottom left

Because my life has been so busy I have not really had the time to take harvesting my sweet potatoes seriously until a few days ago, when I realized that the night temperatures would soon dip below freezing. My first priority was to determine how well the new purple varieties had grown and I wanted to harvest these two varieties first, so that I could compare them to my All-Purple variety. From cleaning out some vines in the area of my Purple Delight sweet potato vines I soon found enough potatoes outside of my garden bed to start filling up a bucket.

A few Purple Delight potatoes I harvested outside of the garden

Soon thereafter came the moment that every gardener either hates or loves: digging to find out what is in the garden bed. Here are a few pictures I took while digging around:

Are there any Sweet Potatoes in there?

Pulling out the first Sweet Potatoes

I think I found something

A closer look (the black thing is a soaker hose)

Exposing a few more potatoes, the next day.

Accessing sweet potatoes sometimes requires me to dig a little

The Purple Delight Sweet Potato Crop

Over time I have developed three main criteria that I aspire to have my sweet potato crop meet: Large production, high quality dark flesh, and marketable size and shape.

This potato turned up to be a bit too big to easily sell

My favorite potato retained its beauty and high quality flesh even at a large size

 As shown in the pictures, the Purple Delight produces well (48+ pounds from one root ball) and the exhibits a very dark purple color. Although the shape and size of roots varied greatly there seemed to have been very few (if any) “woody” roots.

The over 48 pounds of Purple Delight Sweet Potatoes

Overall, I would have to say that I have been very pleased with the Purple Delight sweet potato. Of all people, I would have never dreamed at the outset that the scrawny slips from a battered box would produce so well.





 

Note: Purple Delight is also known as Alabama Purple. I will definitely be doing some taste testing in the future!