Dahlia and Frost

As a rough guide, it is fairly safe to restrict most varieties of giant and large decoratives to three branches on light soils, allowing up to five branches on plants grown on rich soils.

Some growers in fact leave such a pot by each plant until the danger of frost has completely passed. As an alternative a twist of straw may be tied to the stake and teased out to cover the plant at the base. Cardboard boxes may be used-the choice of covering material is almost limitless.

Should the plants become frosted, due to a completely unexpected frost, they may often be saved by spraying with very cold water. This must be done before the sun has risen, or at least begun to shine on the affected plants. The damage caused by frost is clue not so much to the chilling but to the fast expansion of the chilled tissue when the sun’s light falls on the leaves and stems, causing a rupture of the cell walls and a rapid break down of the tissue.

Small decorative and cactus will require little de-branching, unless the plants produce an unduly high number, when it is advisable to thin out the weaker shoots. Again variety and soil considerable bearing on this point, a weak growing variety on light soil for instance should be restricted to no more than eight or nine side branches. Treat miniature varieties similarly.

This practice is a common one in the more northerly counties. In addition to stopping the plant to induce early flowering it is usual, particularly when grown for exhibition, to restrict the number of branches that each will bear in order that perfection of bloom may be achieved.

The actual number that will be allowed to develop on any particular plant will naturally vary in accordance with the size of bloom, the vigour of the variety and the strength of the ground in which it is grown. It must be obvious, therefore, that a very fair knowledge of the capabilities of the dahlias grown, and of the soil, must be acquired.