Fertilising Your Bonsai / Bonsai Feeds

Bonsai Fertiliser : Page 2 of 2

Page 2 of 2:

Fertilising Lime-Hating/Ericaceous Plants

Lime-hating plants such as Enkianthus, Azaleas (Rhododendrons) and Stewartia require regular replacement feeds of specially formulated fertilisers which ensure that their soil pH remains acidic, and ericaceous fertilisers also contain higher levels of chelated iron which is required by lime-hating species to offset chlorosis.

Many Pine species and Juniper species also benefit from monthly 'acid' feeds.

Suitable fertilisers include Miracid or any other fertiliser that is indicated as being specifically for ericaceous or lime-hating plants.

bonsai feed

Solid, slow-release fertiliser cakes.

Solid Fertilisers

Japanese bonsai growers traditionally used solid fertilisers such as small cakes of fish-meal or rape-seed that are placed on top of the surface of the soil, slowly releasing nutrients every time the tree is watered. The primary advantage of solid fertilisers is that they continually supply the tree with small amounts of nutrients and only require replacing every two to three months so they are less time-consuming to apply.

There are now several solid/slow-release fertilizer-brands on the market i.e. Green Dream and Biosorb, both of which are excellent for outdoor bonsai (they tend to leave an odour which makes their use indoors less attractive!)

green dream bonsai fertilizer

Green Dream s low-release fertiliser that is spread across the surface of soil and is dispersed into the soil itself after watering.


If the nitrogen content of the bonsai soil becomes too high it will burn the roots. Always follow the mixing and application rates described on the fertiliser packaging, never mix a higher concentration than is described and do not feed more frequently than is advised. Overfeeding can result in less growth NOT more.

Trees that are dormant or sick should not be fed as they will not consume the same level of Nitrogen and if care is not taken, salt levels in the soil can build up.

It is often recommended that newly repotted trees should not be fed for at least six weeks to avoid burning new roots.

However, there is now much anecdotal advice and some scientific evidence that promotes the advantages of feeding straight after root-pruning and repotting. Immediately after root pruning, a plant will require additional nutrients to grow and repair roots, particularly phosphorous and potassium. A low nitrogen feed would be very beneficial to the plant and unlikely to burn the roots.

Do's and Don'ts of Fertilising

Do use fertilisers regularly; they are essential to the health of your bonsai and produce strong, vigorous growth.

Do check the requirements of individual species; different species can require different quantities of fertiliser at different times of the year.

Don't feed trees when they are not in active growth as the unused fertiliser level builds up in the compost, potentially resulting in an excessive build up of salts.

Don't feed trees that are not growing due to poor health for the same reason; feeding a sick tree is unlikely to encourage it to grow and will do more harm than good.