Potato: A Lot of Tuber in a Little Space

Potato: A Lot of Tuber in a Little Space

Looking to add a nutritional powerhouse to your early season garden this year? One plant that is often thought to be difficult to grow in Florida will surprise many home gardeners. This plant has a long, storied history, having been introduced extensively worldwide, and has invigorated and decimated entire populations. I speak, of course, of the humble potato (Solanum tuberosum), which performs well in our cooler North Florida winter. This member of the Solanaceae or nightshade family can trace its origins to the Andes mountains, where it was discovered by European settlers and brought back to their countries of origin. From there, the potato found success as a food crop and was reintroduced worldwide. This tuber is a big producer, and worthy of a spot in your home garden.

Varieties

The first objective with potatoes is to find a variety that will perform well in our sandy soils and climate. Russets are thought to be the gold standard in potatoes, and while some may be suitable, they are not optimal for Florida gardens. Instead look for some of the later entrants to this market. Several white and red varieties are available which mature quickly and can tolerate environmental conditions in the panhandle. White varieties suitable for this region are ‘Lachipper’ and ‘Sebago’, while the red varieties known to do well here are ‘Red Lasoda’ and ‘LaRouge’. These are compatible with our environment and as such perform well here.

Potato varieties
UF/IFAS photo: C. Hutchinson

Growth Practices

A well-draining, slightly acidic, and loose soil will provide the best environment for maximum yield. As with all gardening, it’s best to have your soil tested well before you plant and make any pH adjustments required early. Potatoes grow from “seed” which are essentially smaller potatoes grown specifically to produce more plants. It’s best to acquire these from a reputable seller and avoid grocery store leftovers, as their variety and disease resistance is questionable. Growth happens from the “eye” of the seed, which may be planted with or without growing roots.  Cut the seeds into smaller pieces, ensuring there is at least one eye per piece, and allow them to sit in a cool, dark environment for a few days to callous over. They are now ready to plant and should be four inches deep, spaced eight inches apart in three-foot rows. Potatoes require two fertilizer applications, emphasizing nitrogen and potassium specifically, as these pass through the soil easily with irrigation. Apply half of the fertilizer at planting with another application approximately 30-40 days later. Application rates vary and are based on yield goals as well as soil test results so check with your local extension agent to discuss application rates. Keep the potatoes evenly moist but make sure not to flood the rows. Finally, there is a unique methodology with potatoes in that you’ll need to add soil to the top of the row when the potatoes poke through. This is called hilling and is crucial to keep the tubers from turning green and producing a toxin known as solanine.

Potato plant with tubers
UF/IFAS photo: C. Christensen

Harvest Time

Your potatoes should be harvestable in about 90-105 days, depending on variety and environmental factors. You’ll be able to tell the plant has matured as the vines will begin to die back naturally. Modern practices have augmented this to include a vine kill which may be performed mechanically or through chemical application. This will force the tubers to mature, allowing the gardener greater control of harvest times and helping to avoid the risk of late-season pathogens. Vine kills are performed between 80-90 days after planting with tubers remaining in the ground for an additional 21 days. All of these time frames are dependent on variety but will produce a more usable and easy-to-store tuber.    

Potatoes after digging
UF/IFAS photo: C. Christensen

Potatoes are a worthy addition to the garden and can provide a lot of nutrient-dense food in a small space. There are a few tricks to growing these tubers, but for what they give back, you’ll find it a very rewarding experience.  For more information, see these Ask IFAS documents. As always, please contact your local extension agent for additional information on this and any topic regarding your gardens and more.

Growing Potatoes

Growing Potatoes

Written by: DeAnthony Price

People love eating potatoes, and farmers love planting them. Traditionally, Valentine’s Day is a known date for planting potatoes. This tradition goes back generations. Potato planting time in North Florida is during the coldest months of January to February, although February 14th is a popular planting day. The taste and texture of homegrown potatoes are far superior to those of store-bought spuds! Garden potatoes also provide a bounty of nutrients. The potato (Solanum tuberosum) is a member of the nightshade family. This cool-weather vegetable typically yields bigger crops in the northern portion of the U.S., however potatoes can be grown as a winter crop in warmer climates.

Potato Varieties

The most popular and successful varieties grown in Florida are based on yield, disease resistance, quality, and adaptability to warm climates. These varieties are white-skinned potatoes ‘Yukon Gold,’ ‘Gold Rush,’ ‘LaChipper,’ and ‘Sebago’, and red-skinned varieties ‘Red Pontiac’, ‘Red LaSoda’, and ‘LaRouge.’ For russet varieties, home gardeners can select varieties that mature relatively early (100-115 days), such as ‘Russet Norkotah.’ Exotic potato varieties are fun and interesting to try since these varieties are hard to find in supermarkets. They are often smaller, taking less time to cook, but are also very colorful, which can increase the nutritional content. Potatoes with bright orange flesh have more carotenoids, and those with red pigments have more anthocyanins, both having health benefits. Other fun varieties include fingerling types and varieties with blue/purple flesh. The ‘All Blue’ potato has deep blue skin and flesh and produces blue flowers. Certified seed potatoes are ideal and can be found at your local feed store or garden center.

Golden and red potatoes
Credit: C. Christensen

Planting Prep: Before Planting

The seed potato needs to be cut into the size of an egg, with at least one eye per section. They must be dried in a cool, dark place for a few days. Plant the sections in a 4-6 inch deep trench that receives full sun, with the cut side down and sprouts facing up. Potato plants are heavy feeders and need nutrition through the growing season. To determine what kind and quantity of nutrients to apply to the soil, get the soil tested by a qualified laboratory. Contact your local Extension office for local fertilization recommendations. Apply a 10-0-10 fertilizer at 7.5 pounds per 100-foot row, both at planting and again 3-4 weeks later, by side-dressing fertilizer about 4-6 inches to either side of the plant.

Growing, Harvesting, Storage

Potatoes are ready to dig in about three months. Since potato tubers push up above the soil surface, the soil needs to be mounded around the stems as the plant grows. Tubers exposed to the sun turn green, making them inedible. Remove the tops 2-3 weeks before digging to “toughen the skin.” After harvesting, potatoes need to be kept in a cool (60-65 degrees F) dark place for 10-14 days to allow any damages to heal. Move them to a final storage location with high relative humidity, good aeration, and cool temperatures (38-40 degrees F). Washed tubers should be allowed to dry thoroughly before storing. Under proper conditions, potatoes can be stored for 3– 6 months or more.

HS933/HS183: Growing Potatoes in the Florida Home Garden (ufl.edu)

Stressed Out Potatoes

Stressed Out Potatoes

 

Typical Hollow Heart condition as seen on this Red Lasoda potato. Image Credit: Matthew Orwat, UF/IFAS

Typical Hollow Heart condition as seen on this Red Lasoda potato. Image Credit: Matthew Orwat, UF/IFAS

One of the most frustrating things about gardening is finding something wrong with a crop that cannot be fixed. I witnessed this last week when checking on a problem with some recently harvested potatoes.

Sometimes potatoes that look perfect on the outside might not be perfect on the inside. Unfortunately, this is the case when potatoes are afflicted by the physiological disorder “hollow heart” or “brown center”.

The disorder that causes hollow heart or brown center in the potato tuber manifests when cells die inside while potatoes are growing too quickly or unevenly, such as when recovering from environmental stress or over fertilization.

Weather extremes during tuber development cause plant stress. Weather conditions that may cause brown center are early season cool nights, which cause soil temperatures to be below the mid-50s for around a week or longer. Soil moisture at 80% or greater may also cause the same brown center symptoms.

Typical brown center t condition as seen on this Red Lasoda potato. Image Credit: Matthew Orwat, UF/IFAS

Typical Brown Center condition as seen on this Red Lasoda potato. Image Credit: Matthew Orwat, UF/IFAS

Hollow heart is typically caused by swings from low to high soil moisture and overapplication of nitrogen. To mitigate this condition, consistent irrigation practices and spit fertilizer applications have been shown to be effective.

Additionally, if hollow heart or brown center is a typical problem for a given growing area, selection of cultivars that are less susceptible to this condition is beneficial, since there is quite a bit of variation among cultivars / varieties.

The final message is one of good news, if brown center or hollow heart is noticed at potato harvest this year, there are steps that can be taken to mitigate this issue for future growing seasons.

For more information, please check out the reference for this article, UF/IFAS publication HS945 “Potato Physiological Disorders—Brown Center and Hollow Heart”

More Gardening Tips for February & March

More Gardening Tips for February & March

Are you “chomping at the bit” to get started gardening this year, but not sure what you can do at this point? Well, good news, there’s plenty of things that can be done whether landscaping or vegetable gardening is your passion.

new potatoes

“New” potatoes grown in Florida. Photo Credit: C. Hutchinson, UF/IFAS

Temperatures can drop significantly in the Panhandle this month, and with short notice. If you want to enhance your flower beds, be sure to use annual bedding plants that can withstand the chill. Dianthus, pansy, viola and dusty miller are some good suggestions to plant. It’s a good time to plant bulbs too. Dahlias, crinum and agapanthus are good choices this time of year. Be sure to provide adequate mulch and water during this cold weather month. There are plenty of trees and shrubs that are beginning to bloom this time of year also. If you’re like me, your allergies will tell you this too. Red maple and star magnolia, just to name a couple, will soon be in bloom.

As for vegetable gardening, the potato is a good choice for Florida gardens. As Americans, we consume approximately 125 pounds per person a year. Potato farming is done commercially in Florida, but mostly with “new” potatoes. These are the small, rounded immature potatoes that have a thin skin and are perfect for low country boils.

It’s February, so it’s Irish potato planting season. The planting season for this cultivar for the Panhandle is from February 1st to mid-March. Sweet potatoes can be planted beginning in late March through June. A hundred pounds of seed potatoes should yield approximately ten bushels. Buy healthy certified seed potatoes from a garden center. Avoid using table stock potatoes. Often, table stock will not sprout successfully. Store bought potatoes are often treated with sprout inhibitors too. This treatment can cause development issues if used as seed potatoes.

Raised beds, at least 6”, are the best way to grow potatoes. Be sure to fertilize the bed soil mixture and fertilize again down furrows when planting. Irish potatoes require copious amounts of fertilizer. For fertilizer, use a general, complete formulation like 10-10-10. Before planting, be sure to dust the seed potatoes with a fungicide to reduce the chance of decay. Plant seed potatoes 3” in depth, at 12” apart and allow for 36” row spacing.

Please take these gardening tips into consideration this month and the next. Spring is just around the corner. Happy gardening! For more information please contact your local county extension office.

Supporting information for this article can be found in the UF/IFAS EDIS Publications, “ Florida Vegetable Gardening Guide” by Sydney Park Brown, Danielle Treadwell, J. M. Stephens, and Susan Webb : http://edis.ifas.ufl.edu/pdffiles/VH/VH02100.pdf and “Growing Potatoes in the Florida Home Garden”, by Christian T. Christensen, Joel Reyes-Cabrera, Libby R. Rens, Jeffrey E. Pack, Lincoln Zotarelli,Chad Hutchinson, Wendy J. Dahl, Doug Gergela, and James M. White: http://edis.ifas.ufl.edu/pdffiles/HS/HS18300.pdf

Supporting information can also be found on the UF/IFAS website under “Florida Gardening Calendar” by Sydney Park Brown: http://solutionsforyourlife.ufl.edu/lawn_and_garden/calendar/pdfs/February_North.pdf

Add Potatoes to Your Florida Garden

Add Potatoes to Your Florida Garden

Potatoes planted in mid-February were ready to harvest in mid-May in Bay County. Photo: Vicki Evans, UF/IFAS Master Gardener

Potatoes planted in mid-February were ready to harvest in mid-May in Panama City. Photo: Vicki Evans, UF/IFAS Master Gardener

A common misconception is that all potatoes come from the Midwest. However, select Irish potato varieties are produced commercially in Florida on over 20,000 acres. Potatoes can also be grown in Florida home gardens if care is taken to select the correct type and recognize proper timing.

Potatoes are a cool season crop and the ideal time to plant in the Florida Panhandle is in January and February. Valentine’s Day is a good target planting date for home gardeners with plants producing tubers after about three months (variety and weather dependent).

The ideal site for potatoes has well-drained soils with a pH range of 5-6. To increase drainage, beds can be formed into hills that are 10-12 inches above the soil. Another option is to grow potatoes in raised beds or containers to ensure the plants will not sit in water during heavy rains.

Certified seed potatoes are available in garden centers. Photo: Julie McConnell, UF/IFAS

Certified seed potatoes are available in garden centers. Photo: Julie McConnell, UF/IFAS

Use certified “seed” potatoes to ensure you are starting with healthy tubers. Cut seed potatoes into egg sized pieces that contain at least one eye each. Allow the cut seed pieces to heal for a couple of days in a cool, dark spot with good ventilation. After healing they can be planted about four inches deep 6-8 inches apart with three feet between rows.

Sometimes potatoes will push to the surface of the soil and will need to be covered with more soil (hilling). If the potatoes are not covered, they can become damaged by the sun and inedible.

Keep your garden weed free to minimize competition with your crop and to also reduce the likelihood of weeds harboring insects or disease that can be harmful to potato plants.

A few weeks after planting seed potatoes, you should begin to see some vegetative (leaves and stems) growth above the soil. Potato plants can grow over a foot tall and are bushy. Small new tubers start to form underground before blooming, but they need more time to bulk up before harvesting. The entire growing process takes between 80 and 115 days from planting to harvest.

Potatoes harvested from container garden. Photo: Julie McConnell, UF/IFASIf you plan to store your potatoes, allow them to remain in the ground for 2-3 weeks after the top of the plant has died to fully mature. If the vegetative portion of the plant does not die on its own the top can be cut to induce maturation of the tubers.

For recommended varieties and more information on care and harvesting please see “Growing Potatoes in the Florida Home Garden.”