THE EFFECT OF NITROGEN AND PH ON THE GROWTH OF CHAMAECYPARIS IN POT

To draw up fertilizer recommendations for conifers in pots, experiments were carried out during two years and at three locations with rooted cuttings of Chamaecyparis lawsoniana ‘Alumii’ on Finnish sphagnum peat.
At one location also other Chamaecyparis cultivars were tested.

The amount of N, the form in which the N was given, viz., Ca(NO₃)₂ or (NH₄)₂SO₄, the pH of the substrate, and at one location the amount of a nitrification inhibitor, were varied.

The effect of all factors mentioned on the growth of Chamaecyparis cultivars was small, both quantitatively and qualitatively.
The amount of N had the greatest effect if the zero N-level was included in the trial.

For optimum growth, rooted cuttings should be fertilized with about 0.25 g N. For Chamaecyparis cultivars, it is unfavourable to give the N as NH₄-N alone.
The currently recommended pH-H₂O for the substrate, 4.8–5.2, needs no revision.
Presented are the contents of mineral nutrients in soil and plant at optimum levels.

Symposium on Substrates in Horticulture other than Soils In Situ

H. Niers

https://doi.org/10.17660/ActaHortic.1982.126.40