Variable

Unit

Optimal

Suboptimal

Unfit

Climate*

Types

Aw, Am, Af

Cw, Cf

Bs, Bw, Cs

Average annual temperature

˚C

22 - 34

16 - 22

34 - 40

<16

> 40

Elevation

msnm

0 - 1000

1000 - 1800

>1800

Average annual precipitation

mm

1200 - 3000

800 - 1200

3000 - 4000

<800

>4000

Soil

Types

-Andosols

-Fluvisols

-Luvisols

-Nitisols

-Acrisols

-Cambisols

-Non-flooding Gleysols

-Non-flooding Vertisols

-Solonchaks

-Flooding Gleysols

-Flooding Vertisols

-Phaeozems

-Arenosols

-Leptosols

-Regosols

-Rendzinas

Soil texture

Types

Medium

Medium and Heavy

Light and Heavy

Soil depth

m

>1

1 - 0.5

>50

Soil pH

Indicator

5.0 - 6.0

4.0 - 5.0

6.0 - 7.5

<4.0

>7.5

Drainage

Types

Good

Good

Deficient