Each plant has specific pH requirements in order to develop harmoniously. The table below shows the pH of compost and soil. The pH up to 6,8 is consider acidic, or sour, pH between 6,8 – 7,0 neutral and above 7,0 bitter or alkaline.

Type of soil/ substrate / compost
pH minimum
pH maximum
Compost (depending on the proportion of potassium)
6,3
8,0
Manure (fully composted stable manure)
6,3
7,4
Old forcing manure (fully composted)
7,0
7,6
Leaf compost (it depends on the type of deciduous foliage)
5,0
6,0
Compost from coniferous needles (depending on the type)
4,0
4,7
Turf ground (depending on the turf)
6,8
7,4
Clay
7,0
7,8
Moss ground
3,5
5,0
Heathland ground (in chunks)
4,0
5,2
Peat
4,0
4,6
Coarse sand
5,7
6,4
Ditch sand
7,4
8,0