Tag Archives: root stock

Garden Lore Friday 31 October

Garden Lore

“Against the uniform sheet of snow and the greyish winter sky the Italian villa loomed up rather grimly; even in summer it kept its distance, and the boldest coleus bed had never ventured nearer than thirty feet from its awful front.”

Edith Wharton, The Age of Innocence (1920)

Garden Lore: Friday 31 October

Root stock can try and make a bid for freedom instead of keeping to its place below ground, even on well established trees, as seen here. I know this is escaping root stock because it flowered white a good two weeks before the froth of pink in the main tree unfurled, as well as coming into leaf earlier. It will need to be removed. Root stock is usually vigorous and prefers its own shoots to the grafted top so will put its energies there first, if it can. From time to time, people contact us saying things like: “I bought a white magnolia but now most of the flowers are pink and we only get a few white blooms”. Escaped root stock is invariably the answer. Keep the base of the plant clear of any fresh growth.

Sometimes you can buy fruit trees which have more than one variety grafted on top – maybe two or three different apples grafted onto the one set of roots. These are designed for tiny town gardens to give a range of different produce or sometimes to give the necessary pollinators in order to get any fruit set at all. That is fine as long as the nursery understands the need to graft varieties with compatible growth habits. If one is stronger than the other, it will take over and the weaker variety is likely to die over time.

First published in the Waikato Times and reprinted here with their permission.

Garden Lore

Sir Frank Crisp’s eccentricities were reflected in his garden. In 1905 Lady Ottoline Morrell visited Friar Park where she found Crisp, dressed in frock coat and top hat, proudly showing his visitors around the garden, which had ‘Sham Swiss mountains and passes decorated by china chamois’. Twenty-three thousand tons of rock were used in the construction of this garden which accommodated an extensive collection of alpine and other rock garden plants.

Alastair Forsyth Yesterday’s Gardens (1983)

graft incompatibility
Graft incompatibility

The odd growth on this tree is a fine example of what is called graft incompatibility. Many trees and some shrubs are grafted or budded – in other words the roots of a different cultivar are used to grow the desired top. There are many reasons to do this. Sometimes dwarfing stock is used to keep fruit trees – particularly apples and citrus – small enough for home gardens. Often a plant will have special characteristics – maybe variegated foliage, bigger flowers, weeping habit – but it cannot be raised true from seed and getting it to root from cuttings may be difficult, too slow or impossible. In that case, it is budded or grafted.

A closely related plant has to be used as root stock and as a customer you are reliant on the propagator or nursery knowing what root stocks to use. If they make a poor choice you can end up with this effect over time. It will be a weak point on the trunk. Where the top and bottom are fully compatible, it is hard to pick the join although it always pays to keep low growth removed in case it is the root stock coming away. It can out-compete the grafted top if left to its own devices.

This is a lime tree, or linden on a London street.

First published in the Waikato Times and reprinted here with their permission.