Vegetables Grown Underground

1. Vegetables Grown Underground Objective: To learn more about importance, propagation, and cultivation of vegetables that are tubers, roots, or bulbs.

2. Importance • For centuries, underground vegetables have been staple crops • Storable for ____________ periods before the advent of refrigeration and long-distance shipping • Last longest in a cool, well-ventilated place that maintains humidity and air circulation • ________________ is a good range, but optimum storage temp depends on particular vegetable • Root cellars were common in dwellings • Today, many use garages or basement storage rooms • Can still find plans for home root storage; they range from very cheap and simple to quite complex

3. General Cultivation Requirements Soil must be: • Deep, friable and well-drained • Fertile • Veggies that are stems or leaves need lots of ________________________ • Those that are roots need lots potassium and phosphorous for synthesis of proteins, carbohydrates and ________________________ Harvesting tubers • Can be harvested immature (“new potatoes”) • Do not store below ________________ • Prompts starch to change to sugar, which causes a sweet taste and brown color when cooked

4. Tubers • Potatoes • ______________________: cover developing tubers with soil • Promotes drainage • Prevents exposure to sun which causes green skin and accumulation of toxins in the tuber • ______________________ culture • Can be grown under 4-6 inches of straw rather than soil • Promotes cooler, more uniform temps and better shape

5. Roots • Taproots • Radishes, carrots, beets, turnips, rutabagas • Cultivation hints: • Plant radishes in with __________________ • Emerge much more quickly to mark row • Help _____________________carrot seedlings break soil crust • Turnips and rutabagas cold-tolerant Brassicas • Were used as a substitute for potatoes • Turnips grow better farther south, rutabagas farther north Turnip Rutabagas

6. Roots • ___________________roots • Sweet potatoes • Morning Glory family; can be an _____________________ • Grow on trailing vines that root at the nodes • Usually propagated from ________________________ (stem cuttings), but can use roots or root cuttings • Easily damaged; have to “_____________________” them • Let dry on the ground for several hours, store in a humid room for 10-14 days so they form a thicker outer skin, and then store them at cool temps • Often called yams, but yams are actually a different species grown only in the tropics

7. Roots • Lateral Roots (continued) • Horseradish • Also a Brassica (mustard family) • _______________________________ comes from a volatile compound called isothiocynate • Becomes apparent when oxidized by saliva or air • Propagated by ___________________________ cuttings • Can be stored in the fridge for several months to prevent further growth, and then planted out again • Most of the world’s horseradish supply is grown in _____________________________, IL

8. Bulbs • Enlarged, fleshy leaf structures that grow at the soil surface and contain a small stalk • Long days promote _________________ formation • Harvest when leaves are ___________% dry and fallen • Garlic • Fleshy leaf structures are called ___________________ • Individual cloves are planted, pointy side up • Hang bulbs to dry after harvest • Good for companion planting with lettuce, cabbage, and beets • Produces a compound called __________________________, which is a natural antifungal and pest deterrent

9. Bulbs • Onions • Fleshy leaves called scales make up bulb • ____________________________ season onions have an intense pungent flavor, but have thick papery leaves for protection and are good for storage • _____________________ season onions are sweeter and milder, but have a high water content and bruise easily • Round sets form flatter bulbs; elongated sets form round bulbs • Although it is trickier to plant onions from seedlings, they are likely to ___________________ longer than those started from sets

10. Changing gears: Legumes Objective: To understand the importance of legumes in multiple capacities; food, forage, and fertility

11. Legumes as Food • Legumes are Fabaceae or Leguminoceae • More than 13,000 legume species, but humans only eat about ________________ of them • Very important to human diet • Protein • Especially where ______________________ is hard to come by • Dietary fiber • Complex carbohydrates called oligosaccharides • May cause gas if not eaten regularly • Vitamins • Second only to grasses (corn, small grains)

12. Legumes as Food • Cultivation requirements • Great diversity of species and subspecies require careful attention and planning • Timing • Peas are ____________________-season, beans are ____________________________-season • Different times to maturity • Pod use vs. seed use • Fresh vs. dry use • Support • ________________________ types are free-standing • _________________________types need to climb • Trellises, fences, and even other plants (Three Sisters) • Fertility • Some provide all their own N, some need more

13. Legumes Provide Fertility • _____________________________relationship between legume roots and Rhizobium bacteria allows N fixation • Bacteria form root nodules and extract nutrients from plant • Healthy, active nodules are 4-8mm long, elongated in shape, pinkish-red inside, and located mostly on primary roots • Unhealthy nodules are smaller, rounder, and pale green inside • Bacteria fix atmospheric N2 into plant-available form… N2  NH4+  NO3- …and promote an increased uptake and concentration of this protein-forming nutrient in the plant’s tissues • This relationship gives legumes their _______________ and soil building properties • _____________________ and __________________ reduce fixation

14. NoduleFormation

15. Other Roles of Legumes in your Rotation • _______________________________manure • Plant in late summer, early fall, or early spring • “Catch” remaining soil nitrogen and fix even more • Kill several weeks before planting • Till into soil, mow down, or kill with herbicide • Increases microbial activity and improves C:N ratio • Releases stored nitrogen for use by main crop • Increases organic matter and improves soil friability • _______________________________ crop • Greatly reduce erosion by covering soil surface and holding it together with their root systems • Act as ______________________ to suppress weeds and hold moisture • Habitat for beneficial insects when inter-planted • Common examples include clovers, vetch, cowpeas, fava beans, field peas, and alfalfa