Tree pH Ranges

As with their wild counterparts, bonsai trees have a tolerance of pH within a certain range according to species. If the soil is outside of the bonsai's pH range, the tree may suffer ill health and lack vigour.

This is a list of tree pH ranges compiled by Marty Klajnowski of San Antonio and originally published in an ABS Newsletter a few years ago; it is fairly comprehensive and a very good indicator of the pH level for individual species.

Acacia 6.5-7.5
Apple 5.0-6.5
Arborvitae 6.0-8.0
Ash 6.0-8.0
Azalea 5.0-6.0
Barberry 6.0-8.0
Beech 6.0-7.0
Birch 5.0-6.0
Bougainvillea 4.5-5.5
Boxwood 6.5-7.5
Camellia 4.0-5.5
Cedar 6.0-7.0
Cherry 6.0-8.0
Cotoneaster 6.0-8.0
Crabapple 6.0-7.5
Cypress, bald 5.0-6.0
Deutzia 6.0-7.5
Dogwood 6.0-7.0
Douglas Fir 6.0-7.0
Eleagnus 6.0-8.0
Elder 6.0-8.0
Elm (Ulmus) 6.0-8.0
Eucalyptus 6.0-8.0
Euonymus 6.0-8.0
Euphorbia 5.5-6.5
Ficus 5.0-6.0
Ficus 5.0-6.0
Fir 5.0-6.0
Firethorn 6.0-8.0
Forsythia 6.0-8.0
Fuschia 6.0-8.0
Gardenia 5.5-6.5
Geranium 7.0-8.0
Ginkgo 6.0-8.0
Grape (Vitas) 6.0-8.0
Hawthorn 6.0-7.5
Hazelnut 6.0-7.0
Hickory 6.5-7.5
Holly (Ilex) 5.0-6.0

Ivy 7.0-8.0
Juniper 5.5-7.5
Lantana 5.5-7.0
Larch 5.5-6.5
Lemon 5.5-7.0
Lilac 6.0-8.0
Mimosa 5.0-7.0
Magnolia 5.0-6.0
Maple (Acer) 6.0-8.0
Mountain Laurel (Kalmia)
5.0-8.0 Myrtle 6.5-7.5
Oak (Quercus) 5.0-7.0
Oleander 6.0-7.5
Orange 5.0-7.0
Oxalis 6.0-8.0
Pine (Pinus) 5.0-6.0
Podocarpus 5.0-6.5
Pomegranate 5.5-6.5
Poplar 6.0-8.0
Privet (Ligustrum) 6.0-8.0
Prunus 6.0-8.0
Quince 6.0-7.5
Redbud 6.0-8.0
Rhododendron 5.0-6.0
Rose 6.0-8.0
Rosemary 5.0-6.0
Sage 6.0-8.0
Spirea 6.0-8.0
Spruce (Picea) 5.0-6.0
Sumac 6.0-8.0
Sweet Gum 6.0-7.0
Tamarix 6.0-8.0
Tuliptree 6.0-7.0
Viburnum 6.0-8.0
Willow (Salix) 6.0-8.0
Wisteria 6.0-8.0
Witch Hazel 6.0-7.0
Yew (Taxus) 5.5-7.0

(Article written and kindly provided by Harry Harrington. )