Crop Coefficient (Kc) Table: FAO-56 Values by Crop & Stage

How to use crop coefficients

A crop coefficient (Kc) converts reference evapotranspiration, the water use of a standard grass surface, into the water use of a specific crop:

Crop evapotranspiration (FAO-56 Eq. 58)

ETc = Kc × ETo

ETo comes from local weather data. Kc comes from this table, adjusted for your climate where needed.

Kc changes through the season, so FAO-56 gives three values for each crop:

Kc ini: the initial stage, from planting to about 10% ground cover. Mostly evaporation from bare soil.
Kc mid: the mid-season stage, from full cover to the start of maturity. Usually the peak.
Kc end: the end of the late season, at harvest or full senescence.

For example, a field of maize with ETo of 7 mm/day during mid-season uses about 1.20 × 7 = 8.4 mm/day.

Crop coefficient table by crop

Values are from FAO-56 Table 12, for non-stressed, well-managed crops in a subhumid climate (minimum relative humidity about 45%, wind speed about 2 m/s), for use with FAO Penman-Monteith ETo. Maximum height is used in the climate adjustment below. Ranges and notes follow FAO-56's footnotes.

Jump to: Small vegetables, vegetables: solanum family, vegetables: cucumber family, roots and tubers, legumes, perennial vegetables, fiber crops, oil crops, cereals, forages and turf, sugar cane, tropical fruits and trees, grapes and berries, fruit and nut trees, wetlands (temperate climate), open water.

Small vegetables

Small vegetables. FAO-56 Table 12, standard climate (RHmin about 45%, wind about 2 m/s). Kc ini values marked * are the group value FAO-56 gives for crops without their own entry.
Crop	Kc ini	Kc mid	Kc end	Max height (m)
Broccoli	0.7*	1.05	0.95	0.3
Brussels sprouts	0.7*	1.05	0.95	0.4
Cabbage	0.7*	1.05	0.95	0.4
Carrots	0.7*	1.05	0.95	0.3
Cauliflower	0.7*	1.05	0.95	0.4
Celery	0.7*	1.05	1.00	0.6
Garlic	0.7*	1.00	0.70	0.3
Lettuce	0.7*	1.00	0.95	0.3
Onions, dry	0.7*	1.05	0.75	0.4
Onions, green	0.7*	1.00	1.00	0.3
Onions, seed	0.7*	1.05	0.80	0.5
Spinach	0.7*	1.00	0.95	0.3
Radish	0.7*	0.90	0.85	0.3

Vegetables: solanum family

Vegetables: solanum family. FAO-56 Table 12, standard climate (RHmin about 45%, wind about 2 m/s). Kc ini values marked * are the group value FAO-56 gives for crops without their own entry.
Crop	Kc ini	Kc mid	Kc end	Max height (m)	Notes
Eggplant	0.6*	1.05	0.90	0.8
Sweet peppers (bell)	0.6*	1.05	0.90	0.7	Grown on stakes 1.5–2 m tall: Kc mid 1.15.
Tomato	0.6*	1.15	0.70–0.90	0.6	Grown on stakes 1.5–2 m tall: Kc mid 1.20.

Vegetables: cucumber family

Vegetables: cucumber family. FAO-56 Table 12, standard climate (RHmin about 45%, wind about 2 m/s). Kc ini values marked * are the group value FAO-56 gives for crops without their own entry.
Crop	Kc ini	Kc mid	Kc end	Max height (m)	Notes
Cantaloupe	0.5	0.85	0.60	0.3
Cucumber, fresh market	0.6	1.00	0.75	0.3	Grown on trellis 1.5–2 m tall: Kc mid 1.15.
Cucumber, machine harvest	0.5	1.00	0.90	0.3
Pumpkin, winter squash	0.5*	1.00	0.80	0.4
Squash, zucchini	0.5*	0.95	0.75	0.3
Sweet melons	0.5*	1.05	0.75	0.4
Watermelon	0.4	1.00	0.75	0.4

Roots and tubers

Roots and tubers. FAO-56 Table 12, standard climate (RHmin about 45%, wind about 2 m/s). Kc ini values marked * are the group value FAO-56 gives for crops without their own entry.
Crop	Kc ini	Kc mid	Kc end	Max height (m)	Notes
Beets, table	0.5*	1.05	0.95	0.4
Cassava, year 1	0.3	0.80	0.30	1.0	Kc end reflects dry-season dormancy.
Cassava, year 2	0.3	1.10	0.50	1.5	Kc end reflects dry-season dormancy.
Parsnip	0.5	1.05	0.95	0.4
Potato	0.5*	1.15	0.75	0.6	Long-season potatoes with vine kill: Kc end about 0.40.
Sweet potato	0.5*	1.15	0.65	0.4
Turnip and rutabaga	0.5*	1.10	0.95	0.6
Sugar beet	0.35	1.20	0.70	0.5	Kc end assumes no irrigation in the last month; up to 1.0 with irrigation or significant rain.

Legumes

Legumes. FAO-56 Table 12, standard climate (RHmin about 45%, wind about 2 m/s). Kc ini values marked * are the group value FAO-56 gives for crops without their own entry.
Crop	Kc ini	Kc mid	Kc end	Max height (m)	Notes
Beans, green	0.5	1.05	0.90	0.4	Grown on stakes 1.5–2 m tall: Kc mid 1.15.
Beans, dry, and pulses	0.4	1.15	0.35	0.4	Grown on stakes 1.5–2 m tall: Kc mid 1.20.
Chickpea	0.4*	1.00	0.35	0.4
Faba bean (broad bean), fresh	0.5	1.15	1.10	0.8
Faba bean (broad bean), dry/seed	0.5	1.15	0.30	0.8
Garbanzo	0.4	1.15	0.35	0.8
Green gram and cowpeas	0.4*	1.05	0.60–0.35	0.4	Kc end 0.60 if harvested fresh, 0.35 if harvested dry.
Groundnut (peanut)	0.4*	1.15	0.60	0.4
Lentil	0.4*	1.10	0.30	0.5
Peas, fresh	0.5	1.15	1.10	0.5	Grown on stakes 1.5–2 m tall: Kc mid 1.20.
Peas, dry/seed	0.4*	1.15	0.30	0.5
Soybeans	0.4*	1.15	0.50	0.5–1.0

Perennial vegetables

Perennial vegetables. FAO-56 Table 12, standard climate (RHmin about 45%, wind about 2 m/s). Kc ini values marked * are the group value FAO-56 gives for crops without their own entry.
Crop	Kc ini	Kc mid	Kc end	Max height (m)	Notes
Artichokes	0.5	1.00	0.95	0.7
Asparagus	0.5	0.95	0.30	0.2–0.8	Kc usually stays at Kc ini during spear harvest; Kc mid applies to regrowth after harvest ends.
Mint	0.60	1.15	1.10	0.6–0.8
Strawberries	0.40	0.85	0.75	0.2

Fiber crops

Fiber crops. FAO-56 Table 12, standard climate (RHmin about 45%, wind about 2 m/s). Kc ini values marked * are the group value FAO-56 gives for crops without their own entry.
Crop	Kc ini	Kc mid	Kc end	Max height (m)	Notes
Cotton	0.35*	1.15–1.20	0.70–0.50	1.2–1.5
Flax	0.35*	1.10	0.25	1.2
Sisal	0.35*	0.4–0.7	0.4–0.7	1.5	Depends on planting density and water management.

Oil crops

Oil crops. FAO-56 Table 12, standard climate (RHmin about 45%, wind about 2 m/s). Kc ini values marked * are the group value FAO-56 gives for crops without their own entry.
Crop	Kc ini	Kc mid	Kc end	Max height (m)	Notes
Castor bean	0.35*	1.15	0.55	0.3
Rapeseed, canola	0.35*	1.0–1.15	0.35	0.6	Lower Kc mid for rainfed crops with less dense stands.
Safflower	0.35*	1.0–1.15	0.25	0.8	Lower Kc mid for rainfed crops with less dense stands.
Sesame	0.35*	1.10	0.25	1.0
Sunflower	0.35*	1.0–1.15	0.35	2.0	Lower Kc mid for rainfed crops with less dense stands.

Cereals

Cereals. FAO-56 Table 12, standard climate (RHmin about 45%, wind about 2 m/s). Kc ini values marked * are the group value FAO-56 gives for crops without their own entry.
Crop	Kc ini	Kc mid	Kc end	Max height (m)	Notes
Barley	0.3*	1.15	0.25	1
Oats	0.3*	1.15	0.25	1
Spring wheat	0.3*	1.15	0.25–0.4	1	Higher Kc end for hand-harvested crops.
Winter wheat, frozen soils	0.4	1.15	0.25–0.4	1	Higher Kc end for hand-harvested crops.
Winter wheat, non-frozen soils	0.7	1.15	0.25–0.4	—	Higher Kc end for hand-harvested crops.
Maize, field (grain corn)	0.3*	1.20	0.60–0.35	2	Kc end 0.60 if harvested at high grain moisture, 0.35 after full field drying.
Maize, sweet (sweet corn)	0.3*	1.15	1.05	1.5	Kc end is for fresh harvest; use field maize values if left to dry.
Millet	0.3*	1.00	0.30	1.5
Sorghum, grain	0.3*	1.00–1.10	0.55	1–2
Sorghum, sweet	0.3*	1.20	1.05	2–4
Rice	1.05	1.20	0.90–0.60	1

Forages and turf

Forages and turf. FAO-56 Table 12, standard climate (RHmin about 45%, wind about 2 m/s).
Crop	Kc ini	Kc mid	Kc end	Max height (m)	Notes
Alfalfa hay, averaged cutting effects	0.40	0.95	0.90	0.7	Season average including cuttings. FAO-56's text quotes 1.05 for this averaged value; Table 12 lists 0.95.
Alfalfa hay, individual cutting periods	0.40	1.20	1.15	0.7	Just after cutting, at full cover, and just before cutting.
Alfalfa for seed	0.40	0.50	0.50	0.7
Bermuda hay, averaged cutting effects	0.55	1.00	0.85	0.35
Bermuda, spring crop for seed	0.35	0.90	0.65	0.4
Clover hay (berseem), averaged cutting effects	0.40	0.90	0.85	0.6
Clover hay (berseem), individual cutting periods	0.40	1.15	1.10	0.6
Ryegrass hay, averaged cutting effects	0.95	1.05	1.00	0.3
Sudan grass hay, averaged cutting effects	0.50	0.90	0.85	1.2
Sudan grass hay, individual cutting periods	0.50	1.15	1.10	1.2
Grazing pasture, rotated grazing	0.40	0.85–1.05	0.85	0.15–0.30
Grazing pasture, extensive grazing	0.30	0.75	0.75	0.10
Turf grass, cool season	0.90	0.95	0.95	0.10	Bluegrass, ryegrass, fescue. 0.95 is for 0.06–0.08 m mowing height; reduce by 0.10 with careful water management.
Turf grass, warm season	0.80	0.85	0.85	0.10	Bermudagrass, St. Augustine. Reduce by 0.10 with careful water management.

Sugar cane

Sugar cane. FAO-56 Table 12, standard climate (RHmin about 45%, wind about 2 m/s).
Crop	Kc ini	Kc mid	Kc end	Max height (m)	Notes
Sugar cane	0.40	1.25	0.75	3

Tropical fruits and trees

Tropical fruits and trees. FAO-56 Table 12, standard climate (RHmin about 45%, wind about 2 m/s).
Crop	Kc ini	Kc mid	Kc end	Max height (m)	Notes
Banana, 1st year	0.50	1.10	1.00	3
Banana, 2nd year	1.00	1.20	1.10	4
Cacao	1.00	1.05	1.05	3
Coffee, bare ground cover	0.90	0.95	0.95	2–3
Coffee, with weeds	1.05	1.10	1.10	2–3
Date palms	0.90	0.95	0.95	8
Palm trees	0.95	1.00	1.00	8
Pineapple, bare soil	0.50	0.30	0.30	0.6–1.2	Very low transpiration; most water use is soil evaporation.
Pineapple, with grass cover	0.50	0.50	0.50	0.6–1.2
Rubber trees	0.95	1.00	1.00	10
Tea, non-shaded	0.95	1.00	1.00	1.5
Tea, shaded	1.10	1.15	1.15	2	Includes the water use of the shade trees.

Grapes and berries

Grapes and berries. FAO-56 Table 12, standard climate (RHmin about 45%, wind about 2 m/s).
Crop	Kc ini	Kc mid	Kc end	Max height (m)
Berries (bushes)	0.30	1.05	0.50	1.5
Grapes, table or raisin	0.30	0.85	0.45	2
Grapes, wine	0.30	0.70	0.45	1.5–2
Hops	0.3	1.05	0.85	5

Fruit and nut trees

Fruit and nut trees. FAO-56 Table 12, standard climate (RHmin about 45%, wind about 2 m/s).
Crop	Kc ini	Kc mid	Kc end	Max height (m)	Notes
Almonds, no ground cover	0.40	0.90	0.65	5	Kc end is before leaf drop.
Apples, cherries, pears: no ground cover, killing frost	0.45	0.95	0.70	4	Kc end is before leaf drop.
Apples, cherries, pears: no ground cover, no frosts	0.60	0.95	0.75	4	Kc end is before leaf drop.
Apples, cherries, pears: active ground cover, killing frost	0.50	1.20	0.95	4	Kc end is before leaf drop.
Apples, cherries, pears: active ground cover, no frosts	0.80	1.20	0.85	4	Kc end is before leaf drop.
Apricots, peaches, stone fruit: no ground cover, killing frost	0.45	0.90	0.65	3	Stone fruit includes peaches, apricots, pears, plums and pecans. Kc end is before leaf drop.
Apricots, peaches, stone fruit: no ground cover, no frosts	0.55	0.90	0.65	3	Kc end is before leaf drop.
Apricots, peaches, stone fruit: active ground cover, killing frost	0.50	1.15	0.90	3	Kc end is before leaf drop.
Apricots, peaches, stone fruit: active ground cover, no frosts	0.80	1.15	0.85	3	Kc end is before leaf drop.
Avocado, no ground cover	0.60	0.85	0.75	3
Citrus, no ground cover, 70% canopy	0.70	0.65	0.70	4	Humid and subhumid climates: increase by 0.1–0.2.
Citrus, no ground cover, 50% canopy	0.65	0.60	0.65	3	Humid and subhumid climates: increase by 0.1–0.2.
Citrus, no ground cover, 20% canopy	0.50	0.45	0.55	2	Humid and subhumid climates: increase by 0.1–0.2.
Citrus, active ground cover or weeds, 70% canopy	0.75	0.70	0.75	4	Humid and subhumid climates: increase by 0.1–0.2.
Citrus, active ground cover or weeds, 50% canopy	0.80	0.80	0.80	3	Humid and subhumid climates: increase by 0.1–0.2.
Citrus, active ground cover or weeds, 20% canopy	0.85	0.85	0.85	2	Humid and subhumid climates: increase by 0.1–0.2.
Conifer trees	1.00	1.00	1.00	10	Well-watered large forests; can be lower due to stomatal control.
Kiwi	0.40	1.05	1.05	3
Olives (40–60% canopy cover)	0.65	0.70	0.70	3–5
Pistachios, no ground cover	0.40	1.10	0.45	3–5
Walnut orchard	0.50	1.10	0.65	4–5	Kc end is before leaf drop.

Wetlands (temperate climate)

Wetlands (temperate climate). FAO-56 Table 12, standard climate (RHmin about 45%, wind about 2 m/s).
Crop	Kc ini	Kc mid	Kc end	Max height (m)
Cattails, bulrushes, killing frost	0.30	1.20	0.30	2
Cattails, bulrushes, no frost	0.60	1.20	0.60	2
Short vegetation, no frost	1.05	1.10	1.10	0.3
Reed swamp, standing water	1.00	1.20	1.00	1–3
Reed swamp, moist soil	0.90	1.20	0.70	1–3

Open water

Open water. FAO-56 Table 12, standard climate (RHmin about 45%, wind about 2 m/s).
Crop	Kc ini	Kc mid	Kc end	Max height (m)	Notes
Open water, under 2 m deep, or in subhumid climates or tropics	—	1.05	1.05	—
Open water, over 5 m deep, clear, temperate climate	—	0.65	1.25	—	Deep water stores heat in spring and releases it in fall. Use with caution.

Typical growth stage lengths (selected US examples)

To turn the three Kc values into a season-long curve, you need the length of each growth stage. These examples are from FAO-56 Table 11, which lists stage lengths for many crops, planting dates and regions. They are general guides only: FAO strongly recommends using local observations of your own crop wherever possible.

Stage lengths in days, from FAO-56 Table 11. Initial, development, mid-season and late-season stages.
Crop	Initial	Development	Mid	Late	Total	Planting	Region
Broccoli	35	45	40	15	135	Sept	California desert
Cabbage	40	60	50	15	165	Sept	California desert
Carrots	30	50	90	30	200	Oct	California desert
Onion, green	30	55	55	40	180	March	California
Tomato	35	40	50	30	155	Apr/May	California
Cantaloupe	30	45	35	10	120	Jan	California
Potato	45	30	70	20	165	Apr/May	Idaho
Sugar beet	50	40	50	40	180	April	Idaho
Beans, dry	25	25	30	20	100	June	Idaho
Peas	35	25	30	20	110	April	Idaho
Soybeans	20	30–35	60	25	140	May	Central USA
Cotton	30	50	55	45	180	April	Texas
Winter wheat	160	75	75	25	335	October	Idaho
Maize, field (grain)	30	40	50	50	170	April	Idaho
Maize, sweet	30	30	30	10	110	April	Idaho
Millet	20	30	55	35	140	April	Central USA
Alfalfa, 1st cutting cycle	10	30	25	10	75	—	Idaho
Alfalfa, other cutting cycles	5	20	10	10	45	June	Idaho
Grapes	20	50	75	60	205	March	California
Hops	25	40	80	10	155	April	Idaho
Deciduous orchard	30	50	130	30	240	March	California
Walnuts	20	10	130	30	190	April	Utah

Adjusting Kc mid and Kc end for your climate

The table is for a subhumid climate with moderate wind. Drier, windier climates raise Kc mid and Kc end; more humid, calmer climates lower them. FAO-56 adjusts them with:

Climate adjustment (FAO-56 Eq. 62 and 65)

Kc = Kc(table) + [0.04 (u₂ − 2) − 0.004 (RHmin − 45)] × (h ÷ 3)^0.3

u₂ = mean daily wind speed at 2 m (m/s, valid 1–6); RHmin = mean daily minimum relative humidity (%, valid 20–80); h = mean plant height (m, valid 0.1–10), from the table above. Use averages for the stage being adjusted. Apply to Kc end only when the table value is 0.45 or more.

Worked example (FAO-56 Example 27)

Maize has Kc mid = 1.20 and h = 2 m.

Humid Taipei (u₂ = 1.3 m/s, RHmin = 75%): 1.20 + [0.04 × (−0.7) − 0.004 × 30] × (2/3)^0.3 = 1.20 − 0.13 = 1.07.
Arid, windy Mocha (u₂ = 4.6 m/s, RHmin = 44%): 1.20 + [0.04 × 2.6 − 0.004 × (−1)] × (2/3)^0.3 = 1.20 + 0.10 = 1.30.

The same crop needs over 20% more water per unit of ETo in the arid, windy site. The crop coefficient calculator applies this adjustment for you.

Frequent irrigation raises Kc mid for low-Kc crops. FAO-56 notes that when a crop is irrigated more often than every 3 days and its table Kc mid is below 1.0, Kc mid can be replaced by about 1.1–1.3, especially where irrigation wets a large part of the soil surface.

Building a Kc curve through the season

FAO-56 builds the curve from straight lines: flat at Kc ini through the initial stage, rising to Kc mid through development, flat at Kc mid through mid-season, then falling to Kc end through the late season. For any day in a rising or falling stage:

Kc on day i (FAO-56 Eq. 66)

Kc(i) = Kc(prev) + [(i − ΣL(prev)) ÷ L(stage)] × (Kc(next) − Kc(prev))

ΣL(prev) is the total length of all earlier stages in days; L(stage) is the length of the current stage.

FAO-56's own example is dry beans in Idaho with Kc values of 0.15, 1.19 and 0.35 and stages of 25, 25, 30 and 20 days. On day 40, in the development stage: 0.15 + [(40 − 25) ÷ 25] × (1.19 − 0.15) = 0.77. The crop water requirement calculator builds the full curve and totals the season's water need.

Before you use the table

Grass reference only. These coefficients are for grass reference ET (ETo). FAO-56 warns against mixing them with alfalfa reference ET. Converting an alfalfa-based Kc takes a ratio of about 1.0–1.3, depending on climate.
Kc ini is a planning estimate. It depends on how often the soil surface is wetted and can range from 0.1 to 1.15. FAO-56 gives a more detailed procedure for Kc ini based on wetting interval and ETo.
Standard, non-stressed crops. Sparse stands, short plants or water stress lower actual Kc. The values assume excellent management and full yield.
Trees after leaf drop. For deciduous trees, Kc end is before leaf drop. Afterward FAO-56 gives about 0.20 for bare, dry soil and 0.50–0.80 for actively growing ground cover.
Local data wins. Local research, extension coefficients or measured stage dates for your crop and variety are more accurate than any general table.

For lawns, the lawn water requirement calculator applies turf coefficients to your local ETo.

Frequently asked questions

What is a crop coefficient (Kc)?

A crop coefficient is the ratio of a crop's water use to the water use of a reference grass surface under the same weather. Multiplying reference evapotranspiration (ETo) by Kc gives the crop's evapotranspiration: ETc = Kc × ETo. A Kc of 1.15 means the crop uses about 15% more water than the reference grass at that stage.

Where do the values in this table come from?

They are from Table 12 of FAO Irrigation and Drainage Paper 56, the standard international reference for crop water requirements. The values are for healthy, well-managed, non-stressed crops in a subhumid climate with a minimum relative humidity of about 45% and wind of about 2 m/s, used with the FAO Penman-Monteith reference ET.

Can I use these Kc values in a dry or windy climate?

Yes, but adjust Kc mid and Kc end first. Arid and windy climates raise them and humid, calm climates lower them. FAO-56 gives an equation for this, and shows that wheat, listed at 1.15, ranges from 1.02 in a humid, calm climate to 1.25 in an arid, windy one.

Why is Kc ini only approximate?

Early in the season most water loss is evaporation from bare soil, so Kc ini depends mainly on how often the soil surface is wetted. FAO-56 says Kc ini can vary between 0.1 and 1.15, and treats the table values as approximations for planning. With very frequent wetting, such as daily sprinkler irrigation or rain, it can approach 1.0 to 1.2.

Can I use these values with alfalfa-reference ET?

Not directly. These are grass-based coefficients for use with grass reference ET (ETo). FAO-56 warns against mixing grass-based Kc values with alfalfa reference ET. An alfalfa-based Kc can be converted by multiplying by a ratio of about 1.0 to 1.3 depending on climate.

What crop coefficient should I use for a lawn?

FAO-56 lists Kc mid 0.95 for cool-season turf and 0.85 for warm-season turf, for well-watered turf under general conditions. It notes these can be reduced by 0.10 where careful water management is practiced and rapid growth isn't needed. Landscape guidance for home lawns often uses lower values, such as UC's 0.8 for cool-season and 0.6 for warm-season grass.

Who built and checked this table

Daniel Reeves, PE, CID

Irrigation Design Engineer & Water-Efficiency Specialist

Licensed Professional Engineer and Irrigation Association Certified Irrigation Designer with more than 20 years in irrigation design, system auditing and landscape water management. Full profile

How this page was checked

Every Kc value and stage length transcribed from FAO-56 Tables 11 and 12 and checked row by row.
Both worked examples recalculated and matched to FAO-56's published results.
Notes checked against FAO-56's own footnotes.

Last reviewed September 25, 2026. Methodology, editorial policy, report an error.

Sources

Allen, R. G., Pereira, L. S., Raes, D. and Smith, M. (1998). FAO Irrigation and Drainage Paper 56, Crop Evapotranspiration. Chapter 6: ETc, Single crop coefficient (Kc), Tables 11 and 12.
FAO Irrigation and Drainage Paper 56. Chapter 5: Introduction to crop evapotranspiration (ETc).
University of California Center for Landscape and Urban Horticulture. Turfgrass Crop Coefficients (Kc).

Crop Coefficient (Kc) Table