Growing Sweet Potatoes in the Backyard

Introduction to growing sweet potatoes in the backyard

The botanical name of sweet potato is Ipomoea batatas. Growing sweet potatoes in the backyard are easy and fun, and this is a great way to enjoy super-sweet tubers that tastes so much better than those you’ll find at the local supermarket. If you’re wondering how to grow sweet potatoes in your home vegetable garden, here we have all the information and advice you need to get started.

A step by step guide to growing sweet potatoes in the backyard of the home garden

Sweet potatoes are grown from slips, which are rooted sprouts from mature tubers. These tender, rooted sprouts can be purchased by mail or sometimes as potted plants at a garden center. Sweet potatoes are starchy tubers that form underground like regular potatoes. But the heart-leafed vine that produces sweet potatoes requires a longer growing season (100 to 140 days) and warmer soil than the kind of plant that produces regular white potatoes. Until recently, that’s made them almost impossible to grow in the colder parts of the country. Now, with short-season sweet potato varieties, such as Georgia Jet, and soil-warming growing techniques, gardeners everywhere can enjoy growing this easy and delicious crop.

In this article, we will let you know the varieties of sweet potatoes, and steps involved in growing sweet potatoes, and some pests and diseases of sweet potatoes, and some tips in growing sweet potatoes, and etc. So, let’s dive into the topic.

Varieties of sweet potatoes

There are some varieties of sweet potatoes listed below:

Beauregard: This popular commercial variety produces a potato with pale reddish skin and dark orange flesh that takes 100 days until it reaches maturity.

Bush Porto Rico: The compact vines yield a potato with copper skin and orange flesh after 110 days. This variety has big yields, so are good for smaller gardens.

Centennial: This type has good disease resistance and is relatively quick to mature, averaging about 90 days to reach maturity.

Georgia Jet: Known for its reddish skin and orange flesh, the Georgia Jet is a good choice for a shorter season because it only takes 90 days to reach maturity.

Steps to grow sweet potatoes in the backyard

You should not miss this: Easy Vegetables to Grow in the Pots.

Here are the steps to grow sweet potatoes in the backyard. And it all starts with the sweet potato slip.

Step 1: Growing slips

Sweet potatoes grow from something called slips.  Those are the green vines that grow out of sweet potato when it sprouts.  They’re taken off and planted in the ground to create a new sweet potato plant.

A single sprouting sweet potato can provide you with at least 15 slips. Those 15 slips create 15 plants, which will give you around 30 lbs or 60 individual sweet potatoes. It may take a few weeks or even a month before you see green growth sprouting from the top of the tuber.

Once you’ve got your sweet potatoes, these are the ways to produce slips:

• Stick toothpicks in the top third of your potato and set it in a jar filled with water so the bottom two-thirds is underwater.
• Place the whole sweet potato on its side in a pot, seeding tray, or shallow container filled with a pre-moistened, high-quality potting mix. Fill the container so the potting mix covers the bottom half of the sweet potato.
• Place your jars or containers of sweet potatoes in a bright, warm spot and wait. The slips typically emerge in a few weeks, but it may take as long as two months. This means you need to plan ahead and start your sweet potato slips about two months before you intend to plant them in the garden.

Step 2: Separate the slips

Once the sweet potato tuber has sprouted, your next step is to separate the sprouts into individual slips that can be planted.

• Take each sprout and very carefully separate it from the tuber by gently twisting it. There may be already a rudimentary root structure attached to the slip.
• Lay each slip into a shallow bowl with the bottom of the stem submerged in water and the leaves hanging over the edge of the bowl. To keep your slips healthy, be sure to keep the water fresh and discard any slip that isn’t producing roots or looks like its wilting.
• When the new roots are about one inch long, the slips can be planted in potting soil. But make sure discard any slip that is wilting or that hasn’t produced any roots; these won’t be viable.

Step 3: Choosing and preparing a planting site

The best soil for sweet potatoes is loose and rich in organic matter. In the garden, mix some well-aged compost into each planting hole and then plant slips 12-18″ apart, burying the stem with soil right up to the first pair of leaves. If your soil is clay, rocky, or compacted, consider raised beds.

• Pick a location with plenty of room for those vines to run
• Dig the area of the garden you will be using to a depth of 8 to 10 inches. Create raised mounds 6 to 8 inches tall and about 12 inches wide. Use fertile, well-drained soil.
• If a soil test indicates poor soil, amend appropriately. Consider natural fertilizers such as compost or manure, as sweet potatoes are extremely sensitive to aluminum toxicity. Avoid high nitrogen fertilizers that promote foliage growth, but often at the expense of tubers.

Step 4: When to plant sweet potatoes

To produce a worthwhile harvest, sweet potatoes need 3 to 4 months of warm temperatures, so the key is to plant them early enough for them to mature properly, but not early enough for them to get killed by a late spring frost. Slips should be planted in warm soil 3 to 4 weeks after the last spring frost, once nighttime temperatures have reached at least 13°C.

Sweet potato plants are sensitive to cold, so they should not be planted outdoors until the soil has warmed to at least 15°C and nighttime temperatures are above 15°C.

Step 5: Taking care for sweet potatoes

For taking care of sweet potatoes you need to consider the following:

Light requirement for growing sweet potatoes in the backayard

Be sure to plant your sweet potatoes in full sun to part shade. Sweet potatoes generally prefer full sunlight but appreciate some afternoon shade in hot, dry regions.

Soil requirement for growing sweet potatoes in the home backyard

Sweet potatoes prefer soil that is well-drained but high in organic matter. Sandier soil is preferable to dense, clay soil. Slightly acidic soil with a pH between 6.0 and 6.5 is ideal. Sandy loam that’s well-draining but nutrient-dense will make this sun-loving tropical vine happiest.

Water requirement for growing sweet potatoes in the backyard garden

Sweet potatoes will tolerate growing in dry soil once established. It’s best to keep it evenly moist with an inch of water once a week. Don’t water your sweet potatoes during the final three to four weeks prior to harvest in order to keep the mature tubers from splitting.

Temperature and humidity

Sweet potatoes should not be planted outdoors until the temperature of the soil has warmed to 15°C. Soil growing temperatures of sweet potatoes should be between 15 to 30°C and an air growing temperature should be between 18 to 35°C. 

Fertilizer for growing sweet potatoes in the backyard garden

Feeding sweet potatoes tend to produce just foliage. You can add compost to the beds before planting the sweet potatoes.

Step 6: Planting sweet potatoes

Sweet potatoes will be one of the last things you plant in your garden. They must go in later than peppers, tomatoes, and other heat-loving plants because sweet potatoes need warm soil as well as warm air.

You can speed up your soil warming by laying a layer of black thermal plastic in your garden bed. It will heat the soil up by as much as 10 degrees which means you can plant sweet potato slips 1-2 weeks sooner than if you don’t use plastic.

• Lay black thermal plastic on the area for planting 2 weeks before setting out
• Dig a hole about 4″ or 5″ deep and 3″ wide by using a small hand trowel
• Plant 1 slip in each hole per square foot with the roots pointing down
• Make sure the slip has contact with soil all around
• After positioning the bottom half will be covered with dirt while the top half with all the new leaves is above ground
• Fill the hole with dirt carefully so that you don’t bruise the new plant
• Gently press surrounding dirt and the plant to set the plant and to remove any air pockets
• Keep the sweet potatoes well watered throughout the summer. Using the plastic eliminates the need to weed

Continue the same process until all of your slips are planted. Planting the slips closer than 1′ together will reduce your yield and produce much smaller sweet potatoes. Don’t fertilize your sweet potatoes at planting time as they don’t require much in the way of nutrients. An excess of nitrogen will encourage leafy growth rather than big tubers.

Step 7: How to grow sweet potatoes

Once your sweet potato slips have been planted in the garden, water them well and continue to irrigate the bed daily for the first week if there has been no rain. After they’ve adapted to their new home, you can reduce watering, but keep in mind that drought-stressed plants yield fewer and smaller sweet potatoes. If you’re not growing them under the black plastic mulch, mulch plants with straw or shredded leaves to reduce the need to water.

Expect the newly planted sweet potato slips to sit for a few weeks as they put on root growth. Once the heat arrives, the vines quickly take off. If the spring weather experiences a setback and cold temperatures are in the forecast, cover your plants with a row cover to insulate them.

For good harvests, do not prune the vines, because they should be vigorous.

Step 8: Harvesting sweet potatoes

The tubers are ready to harvest in about four months. If you like to eat the leaves as greens, you can do so in moderation throughout the season. Be sure to leave enough to keep the plant growing. You can dig your tubers once the foliage starts to yellow. If the foliage is hit by a frost, the tubers are probably still fine. Just don’t let them sit in the ground too long after the tops die back or they could start to rot.

If the vines get touched by frost and start to turn black the sweet potatoes can rot quickly so dig them up right away!

• Cut the tangle of vines away, leaving only a few stubs to let you know where the plants are
• Using a shovel or digging fork, dig them up!  Honestly, the most fun crops to grow are the ones that grow underground because you have no idea what you have until the day you dig them up.
• Be careful when you’re digging them and pulling them out. Sweet potatoes bruise easily

Step 9: Curing and storing the sweet potatoes

Harvesting sweet potatoes don’t end with digging them up.  Once you dig them up you have to let them dry in the sun for a few hours.  Then they need to be brought inside and cured for 10 days and then cured some more for another month or so.

Curing the sweet potatoes

Once you’ve harvested all your sweet potatoes, it’s time to cure them. Curing allows the flesh to sweeten up and heals small wounds or cracks on the skin for long-term storage. Proper curing requires warm to hot temperatures and high humidity. If you only have a small number of tubers and don’t plan on keeping them for more than a few months, quickly cure them at 20 to 25°C over one to two weeks.

Storing the sweet potatoes

Store the sweet potatoes in a root cellar, basement, or other places with a temperature of at least 13°C. If stored at a temperature range of 13–15.5°C with high humidity, the tubers should last for about 6 months.

Store sweet potatoes in an area that doesn’t get below 50 degrees in a container that breathes like a slatted wooden box or a burlap sack.

Pests/diseases of sweet potatoes

Some pests and diseases of sweet potatoes are:

Diseases

1. Alternaria leaf spot and leaf stem blight

Small gray-black oval scratch with lighter centers may occur on stems and leaf petioles and occasionally on leaves.

Control: Destroy all sweet potato crop residue immediately the following harvest; plant resistant or tolerant sweet potato varieties where available; plant only disease-free seed material.

2. Black rot

Causes plant death; stunted plants; wilting plants; yellowing plants; dropping leaves; circular brown-black patches of rot on tubers.

Control: Only disease-free seed material should be planted; transplant material should be collected from plants by making cuts above-ground; seed material should be treated with an appropriate fungicide prior to planting.

3. Fusarium root and stem rot

Growth of white mold, deep, dark rot extending deep into tuber and forming elliptical cavities; the swollen and distorted base of stems.

Control: Select only disease-free roots for seed; use cut transplants rather than slips; practice crop rotation; treat seed roots with an appropriate fungicide prior to planting.

Pests

1. Sweet Potato stem borer

Larvae bore into the stem leading to the storage roots. Feeding in the crown region leads to wilting, yellowing, and dying of plants.

Control: Fallow the land for a few seasons if the infestation is more. Use insect-free planting material. Use pheromone traps to monitor and control the insect.

2. White grub

Including main stem and roots, grub feeds on underground parts. They also feed on tubers by making tunnels. The infected plant becomes wilted and dies eventually.

Control: Provide proper drainage to the soil to avoid excess moisture. Application of biocontrol agents like Bacillus popilliae and B. lentimorbus bacteria kill the grubs.

Some other pests and diseases are:

• Flea beetles
• Sweet potato scurf
• White blister
• Fungal leaf diseases
• Stem rot

Gardening tips to growing sweet potatoes in the backyard

Here are some tips to grow sweet potatoes in the backyard:

• It will take a minimum of 6 weeks for sweet potato planting out. So plan to start the slips prior to that
• Rooted and un-rooted slips can be planted directly in the soil
• Speed up how quickly you can plant your slips outside by laying down thermal plastic
• To prevent vole/mole/mouse damage either grow sweet potatoes in very large pots or grow in a raised bed with wood sides and 1/4″ hardware cloth across the top
• Dig up sweet potatoes when the weather cools in fall
• Cure sweet potatoes at 30°C and 85% humidity for 10 days
• Cure another month at 12-15°C allowing potatoes to develop sugars
• Store long term invented crates or burlap bags at no colder than 10°C

In case if you are interested in Profitable Food Business Ideas.