Growing Geranium Trees

Training slender-stemmed plants to a treelike or standard form is not a new gardening technique. But have you tried it with tree geraniums?

One of the most striking patio displays imaginable is that of a half dozen pots of standard shell pink geraniums against a background of blue iris, double red varieties against a white fence or double whites against a redwood wall.

geranium bloomPin

Any of the larger varieties of zonal geraniums can be trained into treelike forms.

It is a simple matter of removing side shoots as they develop on the plant and any new shoots which appear from below the soil line. The main stem is supported by means of a stake, to which it is tied with nursery tape, twist ties or twine.

Straight Stem Zonal Geraniums

Choose geranium varieties that have thick straight stems and which will develop into large plants.

Plants which bush out are not as suitable because the stems on such plants are apt to be crooked; leave them for ordinary pot culture.

Choice of color is important if the plants are to fill a definite place in the garden landscape scheme.

  • Are your standard geraniums to line the edge of a walk or terrace?
  • Are they to be used to break the harsh lines of a brick or stone wall?
  • Will they accent an entrance or merely act as a background for other plants?

Since geraniums are trained into standards chiefly for the purpose of giving importance to the blossoms, colors must be chosen carefully.

The Cuttings For Starting New Geraniums Trees

New plants can be started by taking long, straight cuttings and rooting them in coarse sand. Place the cuttings in a shady, sheltered place and keep them moist but not wet.

  • Use a sharp knife in taking cuttings
  • Cut them below a joint or node
  • Choose the tips of firm but not woody stems.
  • Remove all but two or three top leaves and any buds

The strength of the cutting is to go towards forming roots, not flowers.

  • Roots will form in from four to eight weeks
  • Once roots form transfer the cuttings to 2 1/2″-inch pots of a leafmold, sand, and garden soil mixture.
  • In about a month, shift the plants to 4″-inch pots with drainage holes
  • Feed with an all-purpose fertilizer.
  • Maximum size of pots to which the standards will eventually be transferred is 6″-8″ inches or the equivalent size in another type of container.

Keep Geraniums Rootbound

Specialists of Geranium plants agree that all pelargoniums should be kept somewhat root-bound for a profusion of bloom. Otherwise, they grow up to foliage instead of producing the best quality flowers.

After the standards have reached a height of about 2′ feet, the top branches should be pinched back to keep the plant compact.

Ultimate height depends upon individual taste and the purpose for which the plants are developed. We have seen standard geraniums 4′ feet high.

Thirty inches is about right for ordinary background purposes. This size is easy to handle, too.

It is most important that the stems be given adequate support, such as a stout bamboo stake. The stems are brittle and will snap off at the slightest strain.

Standard geraniums make an attractive border in a sunny location. Consider burying the pots or plunge them in the bed and make plants appear to be growing in the ground. This makes watering easy, keeps pots from drying out, and permits confinement of the roots.

Submerged pots are easily removed when the planting plan is to be changed, or when the plants have temporarily stopped blooming.

They should then be placed in a shady spot and fertilized well. They will start blooming again in a few weeks.

If the pots seem to be completely filled with roots at the end of the blooming period, run a sharp knife all around the plant about 2″ inches from the main stem, cutting off masses of matted roots.

Remove these roots and replace them in the pot with fresh, enriched soil. Water the plants well and set them aside until they return to their old vigor.