1. Sweet Potato
December 2008

2. Overview
The term “sweet potato” and “yam” are often used interchangeably; however, they are actually two entirely different crops. Only sweet potatoes are grown in the U.S.; yams are grown in the Caribbean and many other tropical areas.
Native to the tropical parts of the South America, and were domesticated at least 5000 years ago.
Grow best at an average temperature of 75°F, with sunshine
Sweet potato is a herbaceous perennial vine, with heart-shaped or palmately lobed leaves, long and tapered root.
The production in 2007 was 825,438 metric ton.

3. Market opportunities Direct Market - on farm stand - U-Dig - internet
About 25 acres of commercial sweet potato production in Kentucky.
Processed sweet potatoes
- baked sweet potatoes
- canned sweet potatoes
- fried sweet potatoes
- sweet potatoes pie
- sweet potatoes biscuits

4. Market opportunities Export Market
Sweet potatoes also can be used as animal feed --- about half of the harvest is used to livestock to support a growing domestic demand for animal protein.
Marketing sweet potatoes in Kentucky.
- Community Supported Agriculture(CSA)
- Organic production
- U-Dig market

5. U.S. Markets and Producers
Plant and food Suppliers
- Central City Produce Co Inc(KY)
- Williamson Produce Inc (NC)
- Justice, Ronald Trucking (AR)
Markets
- Kentucky Farmer’s Market Directory
Dig your own
- ROXBURY Farm (NY)

6. Health and Nutrition Fresh Frozen Energy Kcal 90 100 Selenium mcg 0.2
0.6
Protein g
2.0
1.7
Vitamin A IU
19217
20870
Fat
0.1
Vitamin C mg
19.6
9.1
Carbohydrate
20.7
23.4
Vitamin E
0.7
0.8
Fiber
3.3
1.8
Vitamin K
2.3
2.5
Calcium 38 35
Thiamin
Iron
0.5
Riboflavin
Magnesium 27 21
Niacin
1.5
Phosphorus 54 44
Vitamin B6
0.3
Potassium
475
377
Folate
6.0
22.0
Sodium 36 8
Vitamin B12
Zinc
Pantothenic Acid
0.9
Copper
Manganese

7. Production Characteristics
Sweet potatoes should not be grown on the same land more than once every 3 years
Field high in organic matter should be avoided
Sweet potatoes are usually bedded about 7 weeks before field-setting time
Before bedded, the roots are usually placed by hand to close together but not touching
Sweet potatoes grow well at a soil pH of 5.0 to 6.8

8. Production Characteristics
One crop per year, 90 to 110 days to maturity
Generally planted in the May or June
Grow best on medium to light sandy that are well drained and relatively low in nitrogen
Plant should be spaced 12 to 16 inches in the row and row should be spaced 3 to 3.5 feet apart
Harvest the crop when crop reach the greatest number of 6 to 8 ounces

9. Production Characteristics
Production usually peak in Kentucky at October through January
Clip the vines before harvesting, then they can be harvest with less damage to the crop.
Place them 6 to 8 inches off the floor and 12 to 15 inches from the walls to allow for adequate ventilation
Labor needs per acre are approximately 16 hours for production, 40 hours for harvest and 40 to 50 hours for post-harvest handling

10. Production Characteristics
Weed management
- keep field and borders clear of weeds to prevent seed contamination and enable room for vines to run
Pest management
- few pests and disease attack sweet potatoes
- pest list
grubs weevil
wireworms flea beetle larvae

11. Production Characteristics
Seed management
- seed stock should be held in storage for three to four weeks before bedding at a temperature of 85 to 90 degree F with humidity at 85 percent
Disease management
Black rot Sclerotinia blight
Scurf Fusarium wilt
Nematodes Pox
rotation for 3 or 4 years to deal with all above disease

12. Production Opportunity Cost
Capital Requirement
- Small tractor
- Sprayer
- Digger
- Roll Cultivator
- Land
Labor requirement cost are market rates for agriculture labor (2008 labor rate: $9.00)
Land Opportunity cost(lease value for class A: $100)

13. Revenue Estimates Revenue sources
revenue may vary greatly with price and yield variation
- Market
- U-Dig or U- Pick
- Export
Incentives from the government
- Subsidy
- Tax remission

14. Production Cost Overview
Pre-Harvest Harvest
Plants-seedlings
Transplanting Labor
Machinery Labor
Fertilizer
Herbicide
Insecticide
Fungicide
Irrigation
Tractor/machine
Interest
Tractor/Digger/machinery
Machinery labor
Labor
Boxes/Bags
Packing & Grading
Fungicide
Brokerage
Curing/Storage
Hauling

15. Gross Revenue, Costs, and Return
Item
Unit
Price(dollar)
Quantity
Amount(dollar)
Revenue
acre
17.5
174
Variable cost less labor 1
labor
hour
28.86
14.68
423.67
Total variable costs
Fixed costs
72.79
Total production costs
Interest
20.87
Total costs
Return to land
683.52

16. Export

17. Export Year Total export value Total production value
Export /production 98
10,290
189,532
5.4% 99
10,186
214,754
4.7% 00
11,833
210,351
5.6% 01
11,936
222,658 02
14,787
214,650
6.9% 03
17,466
305,488
5.7% 04
22,236
281,558
7.9% 05
32,026
282,548
11.3% 06
30,720
295,313
10.5% 07
34,976
373,723
9.36%

18. Export
Sweet potato export levels have increased at an average rate of 5 percent annually since 2000
Indicate a strong demand for fresh and processed in the world and anticipated to continue
The ratio will continue to rise and revenue will depend on export in the future

19. Basic Summary Market Opportunity - U-dig - Export - Fresh Market
Advantages of Sweet Potato
- Shorten maturity(only 90 to 110 days)
- Easy to grow, few pests and disease
- lower investment and short time to recover

20. Appendices

21. Appendix - Variable Cost (acre)
Item
Unit
Price
Quantity
Amount
Custom
acre
16.5 1
Fertilizer
Acre
125
Herbicide
35.01
Insecticide
85.24
Seed/plants
209
Other
1313.5
Diesel fuel
gal
1.05
15.79
Repair & maintenance
26.88
Total variable cost

22. Appendix- Labor Cost (acre)
Item
Unit
Price
Quantity
Amount
Operator labor
Hour
9.54
8.9965
85.83
Harvest labor
6.44 25
161
Planting labor 15
96.6
Hand labor
12.473
80.32
Total labor cost
423.75

23. Appendix- Yield, Production, Price, Value and Export
year
Yield per acre
production
Price
Value of production
Volume of export
Value of export 98
148
12,365
15.3
189,532
33,818
10,290 99
147
12,221
17.6
214,754
38,785
10,186 00
145
13,780
210,351
39,170
11,833 01
155
14,515
222,658
44,178
11,936 02
156
12,799
16.8
214,650
49,386
14,787 03
172
15,891
19.2
305,448
56,938
17,466 04
174
16,112
17.5
281,558
61,318
22,236 05
178
15,730
18.1
282,548
96,173
32,026 06
187
16,248
18.2
295,313
82,530
30,720 07
185
18,082
18.3
373,723
89,841
34,976

24. References Health and Nutrition Market Opportunities
Market Opportunities
attra.ncat.org
Production Characteristics

25. References Export Seek management Diseases management
Seek management
Diseases management