Santa Rosa has four series of soil types. In order of decreasing quantity, these are: Lipa series, Guadalupe series, Carmona series, and Quingus series.
The Lipa Series
The Lipa soils span deep as it provides moderately well to well drainage capabilities. The terrain is characteristically undulating to rolling. Both the estimated hydraulic conductivity and infiltration rates are moderate. Specific to the municipality is the Lipa loam type of soil, which has the best physical characteristics among the soil types found in the province of Laguna.
The subsurface soil is characteristically brown to dark-brown in appearance. Other attributes signify it as a mallow, loose and very friable fine granular loam. Its horizontal boundary is smooth and clear. Subsoil is dark brown clay of a friable fine granular tuffessus material with concretions and an irregular and abrupt boundary. The substratum is highly weathered tuff mixed with tuffaceous gravels and concretions. Its boundary is broken and abrupt.
Sugar cane, fruit trees, upland rice and vegetables thrive in this type of soil. Lipa loam is found in Malitlit, Don Jose, Sto. Domingo, Pulong, Sta. Cruz and the southern portion of Dita.
The Guadalupe Series
As a surface layer, the soil is very dark brown to nearly black in colour with an average depth of 20 centimeters. The undisturbed soil is hard and compact and bakes easily when dry. When cultivated, the soil becomes plastic and sticky when wet. When dry, it is coarse, granular and cloddy.
As a subsoil, it is clay, finely granular and sticky when wet. Its color is lighter than that of the surface soil. The soil is underlain with a zone of volcanic tuff material with crevices filled with dark coloured soil leached from percolation through the surface soil. The substratum is primarily massive volcanic tuff. Its topography is undulating to rolling while erosion is most probable.
Guadalupe series covers about 1,296 hectares or 23.38% of the city’s total land area situated in Dita, Pooc, Labas, Tagapo, Balibago, Market Area, Caingin and in the adjacent portions of Macabling, Pulong Sta. Cruz, Dita, Malusak, Kanluran and Ibaba. Soils of this type are best suited for sugar cane.
The Carmona Series
Carmona series soils are derived from the weathered product of volcanic tuff material. Generally, this series of soils is shallow to moderately deep occurring in rolling to strongly rolling contours evidently eroded with slopes. Drainage properties are poor as hydraulic conductivity is moderately slow. In Santa Rosa, there are two soil types within the Carmona series. These are Carmona clay loam and Carmona sandy loam.
Carmona clay loam as a surface layer is brown to light grayish-brown clay loam with few concretions possessing a smooth clear boundary. The subsoil is brown to light-grayish brown clay with tufferneous material and concretions with a boundary comparable to that of the surface layer. Substratum is light yellowish brown to light grayish-brown in color. It is highly weathered tuff with concretions. The topography is gently undulating to slightly rolling with drainage from fair to poor.
Carmona Sandy Clay Loam as a surface layer is pale brown to gray sandy clay with plenty of concretions. It is friable when moderately dry. When wet, it is sticky and pinetic. As subsoil, it is pale brown to yellowish gray plastic clay when wet, with plenty of dark brown and reddish brown concretions. When dry, it is hard and compact. As substratum, it is highly weathered tuffaceous material.
The Carmona Series covers 217 hectares or 3.92% of the city’s land area along the western edge of Sto. Domingo and the western portion of Macabling. Soils of this type are suited for rice, sugar cane, corn, sweet potatoes, bananas and various kinds of vegetables.
The Quingus Series
Quingus series is generally very deep. The well-drained soils occur on level to nearly level terrain as well as on river levees of the alluvial landscape. Hydraulic conductivity is moderately slow as the basic infiltration rate is moderate.
Surface soil is typically light brown. At times, it is pale brown when along the river bank. It is usually loose and very seldom compact, except in undisturbed and higher areas. Subsoil is characteristically light brown with heavier materials than the surface soil.
Quingus series, specifically the Quinga fine sandy loam type of soil covers 2.34 hectares of land along the lakeshore in Sinalhan and Aplaya and in portions of Tagapo, Ibaba, Kanluran, Malusak, Market Area and Caingin. This type of soil is one of the most productive in the Laguna Province where a variety of crops, especially vegetables, can be grown profitably.