Originally arranged 8/21/06 by Andrew Still and updated 7/20/07.
It is hard to convince everybody of this fact, but kale is the swellest of vegetables and Brassica napus is the best of the best. The Russo-Siberian Kales mostly have come out of Northern Europe and Northern Asia, though in the past century they have been shuffled back and forth across the globe like many of our cultivated plant species. Red Russian and Siberian are the two most well known varieties in the United States, however many others have been developed from these lines.
These kales are typically more tender and have a milder flavor than the European “oleracea” kales and are therefore the young leaves are better for salad use. They are always superb as a cooked vegetable when the leaves have grown to full size. Most Varieties are great for used for their springtime sprouts (similar to broccoli raab), although some varieties are specially bred for that use.
Napus kales are super hardy winter survivalists. They are hardy to at least 10°F once established and some sources claim them to be hardy to -10°F and maybe -20°F. Survival at these extra low temperatures may require a good mulch and/or snow cover. There are many factors known and unknown that can effect winter hardiness and there can be no real guarantee for how cold a crop can go. Wind can be an important factor in killing plants and a pattern of freeze thaw freeze thaw can also be detrimental. They Perform best in cool weather but many varieties of napus kales tolerate hot weather. It is widely known that the flavor of Russo-Siberian kale sweetens dramatically after first frost. It can be grown anywhere in the US and even in Alaska.
Being variable in its forms, Brassica napus is divided into three groups or subspecies. The Rutabaga (Swedes in England) is ssp. napobrassica or rapifera and are grown for grown for their swollen stems/roots that resemble turnips (B. rapa). Russo-Siberian Kales and Hanover Salad are ssp. pabularis or pabularia and are grown for their leaves that may resemble those of the European kales (B. oleracea). Winter rape and canola (colza in India) are ssp. oleifera and are grown for their edible leaves, livestock forage, or for the oil rich seed. All have large, flat leaves 12-20 in (30.5-50.8 cm) long and 8-15 in (20.3-38.1 cm) wide, stand 2-4 ft (0.6-1.2 m) when mature, have yellow, cross-shaped flowers with four petals and the small seed develops in sickle shaped pods.
Presently, the species Brassica napus is thought to have originated from a chance hybridization between Brassica rapa and Brassica oleracea. This cross probably happened in European gardens during the Middle Ages. The rutabaga, kale and rape may have all originated from separate chance hybridization between the diverse forms of B. napa and B. oleracea. For example, napus kale could have been derived from B. oleracea ssp. acephala (kale/collard) crossing with the B. napa ssp. chinensis (Asian mustard). The rutabaga could have been derived from B. oleracea ssp. acephala (kale/collard) crossing with the B. napa ssp. rapifera (turnip).
The red Russian type of kales may have a different story. Tim Peters of Peters Seed and Research did an experiment to retrace the evolution of B. napus. He first crossed a Chinese cabbage (B. rapa) with a European kale (B. oleracea). He did these crosses with a bud pollination technique, which he says “lets the two species have more time to get to now each other”. After the first cross the result was a beautiful Siberian kale (B. napus). then he crossed in black mustard (B. nigra). This resulted in the red Russian type (B. napus?) with its distinct color and leaf shapes. So some of the B. napus species are two way mix-ups and some are three way mix-ups. How wonderful! This throws a wrench of doubt into the machine of the probable genealogy of plants, such are the ways of science.
Classification Information for Brassica napus ssp. pabularia
Kingdom Plantae (Plants)
Subkingdom Tracheobionta (Vascular plants)
Superdivision Spermatophyta (Seed plants)
Division Magnoliophyta (Flowering plants)
Class Magnoliopsida (Dicotyledons)
Family Brassicaceae (mustard family)
Genus Brassica (mustard genus)
Species Brassica napus (rape species)
Variety/Subspecies pabularia (Siberian kales)
Botanical Epithets: nap = turnip; apus = stalk-less; pabularia = of fodder
Seed Sowing and Transplanting:
Spring - Sow indoors in march then transplant when the soil can be worked.
Summer - June through august 15 th . Just after the 4 th of July is a good time.
Fall / Winter – six weeks before the first frost so that the plants can become established before winter. Plants are surprisingly hardy when small but may not feed you until spring.
Direct Sowing – Anytime after danger of hard frost has passed once the soil can be worked and once the soil has warmed up a bit, or at least six weeks before the first frost.
As a fall/winter planting it may follow in the same bed after green beans, peas, potatoes or some other planting that has occupied the ground through summer. Kale is a biennial and it’s seed stalks can reach 6 feet and may flop over. This is a long time to occupy an area and it may shade nearby plants. Plan accordingly.
- 215 seeds/gm or 6,000 seeds/ounce. (Wild Garden)
- 300 seeds/gm or 8,400 seeds/ounce. (Territorial)
- 355 seeds/gm or 10,000 seeds/ounce. (Jevons)
Days to emergence:
3-8 Days Minimum or 5-15 Days maximum
Legal germination standard:
Soil and Fertility:
All kales are fairly heavy feeders, however they tolerate low fertility better than other brassicas (like cabbage and cauliflower). If under fertilized kale plants will grow smaller and slower but still retain good overall plant health. Be thoughtful with the fertility issue. Pests such as aphids can zero in on kale when stressed. Too much fertility can cause problems too. Most sources suggest to amend well with a rich compost or composted manure or use 1/4-1/2 cup of a balanced fertilizer per plant. As with other Brassicas, early varieties may require more soil nutrients than the later maturing varieties. They will Tolerate a pH range of 4.2 to 8.3, but prefers somewhere closer to 7 pH. The application of agricultural lime is advised if the soil is naturally acidic, as it tends to be in the pacific northwest. The plants prefers sandy/light, loamy/medium or clay/heavy soils. They Prefer well-drained soil, but they will grow in heavy soil.
Biointensive – 15 in. equidistant, 84 plants/100 sq. ft. in raised beds.
Traditional – sow 1-2 in apart in rows 24 in apart. thin to 16-24 in. Thin at 3rd true leaf and use thinnings in salad, leaving the strongest plants.
Moderate. Do not over-water to an extreme sogginess and do not let the plants wilt heavily due to lack of water. While growing best in moist soil, some varieties are more tolerant of temporarily water-logging and/or drought.
Full Sun/Partial Shade (light woodland), Full Sun is optimal.
Cold temperatures below (-4°C) may either kill or injure seedlings. However, temperatures of -2°C has no affect when the plants are more than one month old (Plants for a Future).
A mulch applied in cold weather will help plants live through very cold temperatures and will help plants stay vigorous to promote good growth in the early spring.
Pick when leaves are large enough for raw salad use or pick when outer leaves are 6-14 inches long for cooking greens. Avoid picking the smallest inner leaves to not damage the growth end. Pick early in the day and cool quickly by dunking in cold water. Store as close to 100% humidity and 32°F as possible. Usually at least a 17 week harvest period, weather dependent.
Biointensive – 114#/100 sq. ft., 0.9-1.8#/plant
Average US -16#/100 sq. ft. (Jevons)
Pests and Diseases
All Kales are less susceptible to insect and disease damage than their cousin brassicas (like cabbage, broccoli and cauliflower) and napus kales are no exception. Here are a number of problems that might arise or not arise at all.
Aphids – May infest plants rapidly when vigor is low, as in the early spring. Common when plants are young and when flowering and seed formation has begun. Avoid by transplanting plants that have not been stunted and growing healthy plants in fertile soil. Most infested plants will pull through when vigorous growth begins. Avoid by planting out later in the season when aphid populations are at their low. Control with Insecticidal soap, hot pepper wax, a hard spray of water. Balance formative forces with horsetail tea (Storl). Encourage predatory insects with insectary crops.
Fungus Gnats – mainly a problem in greenhouses. Can slowly kill young seedlings or set them back in growth drastically. The larva eat organic matter in the soil and love brassica seedling roots.
‘Cabbage White’ Larva/root maggots/loppers/cabbage worm – exclude pests with row cover/fleece such as reemay or agribond. Use summer insect barrier netting or mosquito netting if temperatures are too hot for row covers.
Flea Beetles – exclude pests with row cover/fleece such as reemay or agribond (this is not always effective). Use summer insect barrier netting or mosquito netting if temperatures are too hot for row covers. Predatory nematodes may be an effective deterrent, but must be applied every year. Avoid growing during time of peak beetle population.
Symphylans – Tiny white centipedes that can do lots of damage to roots. They tend to avoid healthy plants, but not always.
Club Root – An infection that causes white club-like swollen roots. This hinders the plants ability to take up water and nutrients, generally stunting growth. In severely infected plants, it will cause severe wilting even when soil is moist and eventually will kill the plant. Some varieties are more resistant than others. Napus is not as affected as other brassica species. This disease is virulent once established and extremely difficult to eradicate.
Damping Off – Young plants fall over and begin to wilt. The stem looking pinched and rotten at the soil surface. It is mainly a problem with young transplants in flats, especially in greenhouses, and is avoided with good air circulation and dry soil surface on cool evenings.
All B. napus (including rutabagas, napus kale, and rapeseed) are inbreeding, although they do a lot of cross pollination between plants. Unlike B. oleracea it is possible to self a single plant without much inbreeding depression and B. napus does not have a self- incompatibility mechanism. The flowers are perfect and are primarily crossed by insects. Due to this, any varieties of B. napus should be isolated by one mile or through other methods such as caging or time isolation. The plants may flower for 2-3 months and this make time isolation difficult. B. napus can be crossed with other brassica species however this must be done with hand bud pollination before the flowers have opened. Natural crosses between species are very rare and although they do happen, they are often not noticed or are discarded before they are fully seen.
First grow the plants as normal for food production and harvest as much as desired as long as the growth tips are not damaged. Because they are biennials (flowering usually starts in April for overwintered plants) they must be overwintered or dug and stored in a cooler or root cellar in extreme climates. This is usually done in sand or sawdust filled crates at 32-40 F and 90-95% humidity. Plants can be overwintered outside in almost any climate if a heavy mulch is applied. Digging and replanting the plants is always useful if you want to inspect the root system of each plant for selection purposes. Only save seed from top quality plants and a culling percentage of over 50% is common and beneficial. It is wise to grow at least 10-50 plants to check for off types and to preserve the genetic diversity of the population.
The seed stalks are 3 feet tall or more and provide excellent forage for bees and beneficial insects. Harvest the seed pods after they have turned tan and dry. Cutting down the entire plant and letting it dry further for a day or two can be done when a large percentage of the seed pods are ripe. Thresh the pods by dancing or jumping on the plants placed on a tarp. Remove the bulk of the shattered plants and then winnow. Winnowing can be done in a breeze or with a fan in order to blow away the chafe and leave behind the seeds. Continue to dry the seeds out of direct sunlight on a flat well ventilated pan, tarp or surface. When dry store safe from insects and rodents in a dry cool location or in an airtight container if the seed is very dry.
5 years maybe more if stored under normal ideal conditions. 10 years or more if dried properly and frozen.
- 3.8 lb/100 sq. ft. Max yield (Jevons)
- I heard Frank Morton say that predicting the seed yield of a brassica crop can be a “crap shoot”.
The Leaf is eaten in Spring, Summer, Fall and Winter (for best flavor). They may be eaten raw, in salad, steamed, boiled, soup, saute, stir fried or roasted. The young flower shoots (napini/raab) are eaten in spring and are very sweet, can be cooked like and have the texture of broccoli or asparagus. They may be eaten raw, in salad, steamed, boiled, soup, saute, stir fried or roasted. Oil made from the seeds can be used as a cooking oil or salad oil. Be warned that The oil contained in the seed of some varieties of this species can be rich in erucic acid which is toxic. Although, modern cultivars have been selected which are almost free of erucic acid. The seed can be used to start sprouts to be used the same as alfalfa sprouts. The seed can also be used as a mustard flavoring.
The root is emollient and diuretic. The juice of the roots is used in the treatment of chronic coughs and bronchial catarrh. The seed, powdered, with salt is said to be a folk remedy for cancer. Rape oil is used in massage and oil baths, it is believed to strengthen the skin and keep it cool and healthy. With camphor it is applied as a remedy for rheumatism and stiff joints. (Plants for a Future)
The seed contains up to 45% edible semi-drying oil. This oil can be used as a luminant, lubricant, in soap making, fuel for diesel engines etc. (Plants for a Future)
Naturalized Range and Habitat:
Wild populations of Brassica napus are found throughout Europe and the Mediterranean (including Britain), India, most states in the US and probably many other countries. Its preferred habitat can be the banks of streams, ditches and arable fields. (USDA)
This is probably the nutrition information for B. oleracea kale, though it may be very similar.
128 calories/lb.,14.1 grams of protein/lb., 601 mg calcium/lb., Very high amounts of vitamins and minerals. (Jevons)
Leaf Kales Varieties
The seed sources below are outdated and should only be used for historical reference.
Bear Necessities – A collection of different skeletal leaf kales. Derived from Russian and Siberian kales (B. napus) crossed with mizuna (B. rapa). A great cold tolerant salad mix item that is mild and very sweet. The leaf shapes are completely unique with a range of leaf colors. Origin: Bred by Tim Peters, Peters Seed & Research, Riddle, Oregon.
- Source: 2006 PSR; 2015 Adaptive Seeds.
Blue Siberian – Siberian type with waxy smooth leaves.
- Source: 1998 Se2 (not available commercially since 1998)
Budget Cuts – Heavily dissected finely cut leaves are very bright and shiny green. Similar to Bear Necessities. One of the best baby leaf Kales to come out of the PSR breeding program. Result of crosses between B. napus and B. rapa, made to create a more hardy salad green. Origin: Bred by Tim Peters, Peters Seed & Research, Riddle, Oregon.
- Source: 2006 PSR
Dwarf Siberian (German Sprouts) – 60-70 days. Broad thick plume-like blue gray green leaves with slightly frilled edges. Hardy and very productive. Not as curly as scotch kales. The Plants grow 12-16″ tall and 24-36″ wide.
- Source: 2004 Bo19, Hig, La1, Sau, WI23; 2006 baker creek
Frilly Kale – Salt Spring Seeds claims this is Brassica oleracea kale but also claims that it is a sport of Russian Kale. Seedlings appear normal for the first month, then start producing green leaves so frilly along their edges that they resemble curly parsley.
- Source: 2006 Salt Springs Seeds Canada
Greenpeace – 32 days. Rare Russian strain, greenish blue plants purple stems, highly variegated leaves. Origin: Greenpeace experimental farm on Denman Island off British Colombia.
- Source: 1998 Se8 (not available commercially since 1998)
Gulag Stars – A mix of Russian and Siberian kales from the original Gulag. Contains some completely unique leaf types and incredible colors. Same great Brassica napus eating quality. Very adaptable and diverse population. Seems to have a bit of B. rapa mustard mixed into its genetic make up. Origin: Bred By Tim Peters at Peters Seed & Research in Riddle, Oregon.
- Source: 2006 PSR; 2013 Adaptive Seeds.
Hanover Salad (Meyer’s Brand Spring, Plain, Smooth, Spring, Spring Sprouts) – 30-90 days. A fast growing, cold hardy, Siberian kale that is said to actually be a rape. Slow to go to seed in spring. The scalloped edged, smooth leaves have the best eating quality when young and tender. The leaves form a rosette that is similar to that is similar to turnip greens, but the root is not tuberous. Can be Sown in Spring or later and overwintered. The leaves are used as cooking greens and in salads.
- Source: 1998 Abu, C13, So1, SOU, Wet. 2004 Cl3, Ho13, ME9, So1, SOU, Wet.
Long Seasons (Late Hanover, Long Season Slow seeding) – 75 Days. Smooth, notched leaves. Cold hardy and will yield late fall or early spring harvests if sown in August or September. Later to mature than Spring Kale due to its slow growth, but it goes to seed later than other varieties. May be the same or very similar to Hanover salad.
- Source: 1998 Abu (not available commercially in 2004)
Long Standing Siberian – Last offered Commercially in 1991.
Red Russian (Ragged Jack, Russian Kale, Canadian Broccoli) – 25 days baby, 50-60 days mature from transplant. Stems and veins are red/purple and the leaves are deep gray/green. Flat leaf with toothed edges. Vigorous plant grow up to 18-36 inches tall. Hardy to -10F. Used as in salad or as a bunching green. [Origins in Russia and may predate 1865. A late variety that is extremely resistant to cold with leaves harvested all winter. Flavor being improved by frost. (Koko)] [Documented since 1885 and reintroduced by Canadian herbalist Betty Jacobs in 1977. (SSE)].
- Source: Widespread availability
Red Ursa – Selected among the 5 Best New Vegetable Introductions of 1997 in the National Gardening Trials. Combines the broadleaf frills of ‘Siberian’ with the color of ‘Red Russian’. Tender, good bulk and flavorful for salads. Bolting purple stems of overwintered plants are very sweet and colorful for salad or for light cooked like asparagus.
- Source: 2006 So6, Sh9
Siberian (Early Siberian, Siberian Curled, Early Curled Siberian) – 60-70 Days. Extremely hardy, vigorous, rapid growing. Blue green, huge, feather shaped, slightly curled leaves. Non heading 12-16 in leaves. Spreading plants sow in spring or fall. Popular in the south. Light frost improves tenderness and flavor, often used for stock feed.
- Source: 2004 lots of sources
Siberian, Dwarf Improved – Can be harvested later into the spring than other varieties because it is slower to go to seed. The very frilly dark green leaves form a 24″ rosette.
- Source: 2007 Ter
Spring Sweet – A selection of the red Russian type that is sweeter in the spring. Oak shaped leaves have less color than others. From PSR breeding Program.
- Source: 1998 PSR not currently commercially available.
True Siberian – 70 days. 24-30″ tall. Extremely cold hardy, fast growing plant with large, frilly, blue-green leaves on non-heading sprawling plants. Can be picked through winter in many areas. Huge root/stock with many growth points. semi-ruffled leaves. Possibly the most productive kale.
- Source: 2007SOC, PS; 2014 Adaptive Seeds.
Western Front – This Red Russian kale mixture has survived a variety of growing conditions that killed all Scotch kales and over 90% of everything Russian or Siberian. Eating Quality is quite good. Up to 50% will regenerate from base of plants for up to 4 or 5 years in wild plantings. Seed Origin: PSR Kale Breeding Program.
- Source: 2006 PSR, BG; 2014 Adaptive Seeds.
Wild Garden Kales – Survived 10F lows in Eugene, Oregon 2006. The mother gene pool from which all Frank’s wild garden variety of napus kales have been derived. Originated as a cross between ‘Red Russian’ and ‘Siberian’ ca. 1984. Intended for mid-July-Aug sowing, fall cropping, and successful overwintering in milder climates to produce copious leaves and “napini” of various shapes and hues. A genetic gold mine for farmers who wish to select strains adaptable to their own farm environment.
- Source: 2006 WGS, Ter
Wild Red – 55 days. Variation on red Russian. 2 foot plants. Silver green foliage overlain with bright red on the stems and leaf joints. Extremely hardy and productive.
- Source: 1998 Hud, Ni1
Winter Red – A red Russian type developed by Tim Peters of Peters Seed and Research for good uniform color and cold tolerance. A tender salad kale that is said to have a little wild mustard in its sap. Works well in a crop scheme with other kales to supply harvests from early fall – spring. Napini from this variety is a month ahead darker red and thinner than other napus kales. A vigorous Red Russian kale that colors up well even before cold weather, but especially after cool weather. The oak-leaf shaped leaves of this kale are more deeply cut than some other common strains of Red Russian kale. Excellent for salad greens when leaves are thumb size; larger leaves make delicious and nutritious cooked greens. Origin: developed by Tim Peters, Peters Seed and Research, Riddle, Oregon.
- Source: 2006 Ter, PSR
White Russian – 50-60 days. Judged most cold hardy kale in trials at Garden City Seeds, Montana 1995. Has a delicate sweet flavor and voted the best tasting among farm crews at Garden City Seeds and at Gathering Together Farm. Tolerates saturated soil better than other kales, lone survivors in two flood years and the annual low spots. Leaves are dissected like Red Russian, but with whitish stems and veining. Very vigorous growth. Origin: Developed by Frank Morton, Gathering Together Farm, Philomath, Oregon.
- Source: 2006 WGS, SOC, HMS, Ter
Kale Raab (Napini) Varieties
Napini kales or kale raab are planted in the fall and overwintered to produce buckets of sweet and tender flower shoots once day length exceeds 12 hours in March. Hardy against frost all the way through spring, it is a great early season food source through the “Hungry gap”. All varieties of B. napus produce great raab but the following varieties are excellent for the purpose.
Purple Napini (Purple Rapini) – [Flat grey/green leaves with purple stems and veins. Not as sweet as leaf kales but the snappy green shoots are thick and doubly sweet. The primary shoots are tender, up to 18 in long and are used like Raab, broccoli, or asparagus. The dozens of smaller shoots that follow are great in salads. Bred by frank Morton of wild garden seeds.(WGS)]
- 2006 source: WGS
Hot Shot Mix – [A Mix of crosses between Purple Napini kale and other napus leaf kales. Mix combines big napini traits with attractive and sweet leaf traits in the same gene pool. Good selections. (WGS)]
- 2006 source: WGS
Russian Hungry Gap Kale – a very rare variety preserved in the Heritage Seed Library’s Seed vault in Ryton, England. 2014 Adaptive Seeds.
B. napus as animal forage
Establishment: Apply appropriate lime and fertilizer prior to planting. To control weeds and grasses, use a burn program to benefit establishment. Sow seeds after the soil reaches 55F or higher. Brassica forage crops may be seeded alone or with grasses.
Seeding: 1/4-1/2″ deep in well prepared firm seedbed, at a rate of 3-4 lbs/acre.Soil: Best in well drained, fertile soil with a slightly acidic pH between 5.3 and 6.8.. With their extensive root system, brassicas have very good drought tolerance once established.
Caution: If proper management is not practiced, health problems may occur in livestock from pasturing high protein, low fiber forage brassicas. Avoid feeding brassicas that are flowering and 80% brassica forage is best.
Dwarf Essex Rape has a high amount of leaf for the amount of stem and the stems are very palatable. After a 75 day establishment period it can be cut or grazed every 30 days. The Forage that is produced may contain 18-20% crude protein. It has great cold hardiness that makes grazing or harvesting late into the fall possible.
Siberian Kale is a very palatable and very high yielding forage crop. It can be cut or grazed summer through fall. It is appropriate forage for sheep, beef and dairy cattle. Siberian kale has great lodging resistance and is ready to graze 70-90 days after it is planted.
2 big cloves of garlic, minced
1 pound kale (about bunch)
2 teaspoons sesame seed oil
2 tablespoons water
1 teaspoon soy sauce
2 teaspoons toasted sesame seeds
Salt and pepper if desired
Mince the garlic cloves. Wash the kale and shake it over the sink. It should remain a little wet. Remove and discard the stems from the kale and tear it into bite-size pieces. Save the stems for another use, such as vegetable stock.
Heat the sesame seed oil in the skillet over medium-low heat. Add the minced garlic to the hot oil and sauté for about 20 seconds. Add the kale and water to the garlic and oil, and cover the skillet.After 1 minute, stir the kale, then re-cover. After 1-2 more minutes, when the kale is wilted, stir in the soy sauce and sesame seeds. If desired, add salt and/or pepper to taste.
Ashworth, Suzanne, Seed To Seed
Deppe, Carol, Breed Your Own Vegetable Varieties
Garden Seed inventory 5th edition (GSI5), 1998, Seed Savers Exchange
- Information for 18 varieties of napus kales, mixed up with the oleracea kale section.
Garden Seed Inventory 6th Edition (GSI6), 2004, Seed Savers Exchange
- Information for varieties of napus kales, mixed up with the oleracea kale section.
Jevons, John, How to grow more vegetables 5th edition,
- little information on kales but tons of information on general Bio-intensive gardening
Seed Savers Yearbook 2006 (SSYB)
Dominique Guillet, Seeds of Kokopelli Kokopelli,
- A manual for the production of seeds, A directory of heritage seeds
Storl, Wold D, Culture and Horticulture, 1979, biodynamic literature
- no specific information on kales but tons of other related information about general biodynamic gardening.
Colebrook, Binda, Winter Gardening in the Maritime Northwest, 1989, Sasquatch
- one of the few winter gardening books and some of the best information on the subject. Contains a some information on oleracea and napus kales.
Bountiful Gardens (BG) www.bountifulgardens.org
High Mowing Seeds (HMS) www.highmowingseeds.com
Johnny’s Selected Seeds (JSS) www.johnnyseeds.com
Peters Seed And Research (PSR) www.psrseed.com (No Longer in Business)
Salt Spring Seeds www.saltspringseeds.com
Seed Savers Exchange (SSE) www.seedsavers.org
Seeds of Change www.seedsofchange.com
Territorial Seed www.territorial-seed.com
Wild Garden Seed www.wildgardenseed.com
New Century Seed & Steyer Seeds, Web site (NSC)
Permaculture Information Web
Plants For A Future
Purdue University Center for New Crops & Plant Products
USDA Natural Resources Conservation Services Plant Database