Leaves of deciduous trees are the stars of the garden at this time of the year. Flowers are the main contributor to colour in the garden during the spring and summer. In autumn the main spectacular colour contribution comes from leaves, berries and the bark of certain trees. The decrease in sunlight produces a change in the chemistry of the leaf. Sugars are trapped in the leaf and these lead to the production of pigments, which are the chemicals responsible for autumn red colours. A warm wet spring, sunny summer and warm sunny autumn days with cool nights like this year will produce the most brilliant autumn colours. The wet and windy conditions over the last week has removed most leaves from their branches. Leaves are retained longer on trees exposed to bright street lights in towns and villages. The following are some plants with great autumn leaf colour.
Liquidambar (sweet gum) is a deciduous tree that is grown for its attractive maple-like leaves that produce gorgeous shades of red, orange or bronze in the autumn. It can be grown as a specimen tree in large gardens and can grow up to 40 feet tall. It produces inconspicuous flowers in late spring. Mature trees have a nice rough grey, furrowed bark.
They grow best in moist, deep, well-drained acid or neutral soil. Grow in full sun for best autumn colours. Liquidambar formosana, native to China, has red-tinted leaves in spring that turn red in autumn. Liquidambar styraciflua ‘Argentovariegata’ has green leaves with a white margin.
Berberis is a large family of evergreen and deciduous shrubs that are often grown as a hedge. Varieties of Berberis thunbergii are the most commonly grown berberis. Berberis thunbergii ‘Rose Glow’ produces red purple leaves flecked with white in summer. A few frosty nights produces glowing red colour on the leaves. Berberis are very hardy plants that will grow in almost any well-drained soil in full sun or partial shade. Old leggy plants respond well to a hard pruning in spring.
Cotinus (Smoke Tree) are deciduous shrubs that are grown for the colour of their foliage. Cotinus coggygria is a bushy shrub with dark purple foliage in spring. In autumn the leaves change to scarlet. The plant is fully hardy and will thrive in most garden soils. In small gardens the plant can be kept in check to reduce its size by pruning in late winter or early spring.
Japanese acers are widely grown in gardens for their attractive foliage. Many of the palmatum varietes have large bronze leaves that turn a brilliant red in the autumn. Japanese maples like a well-drained soil with shelter from wind, especially in spring when the new foliage is emerging. They prefer a slightly acid soil to give the best colour but they will grow well in lime soils also. They can be grown in pots and containers, shelter from cold winds is the one thing they require.
Coprosma is a group of tender evergreen shrubs that are natives of New Zealand. They are mainly grown for their attractive foliage, which is variegated in many species.
Coprosma repens ‘Pink Splender’ has brilliant dark-pink tones on the leaves that are more pronounced in cold weather. The plant likes a neutral to acid soil that is moist but well drained. The plant is not fully frost hardy so it will only survive in mild regions.
Parthenocissus (Virgina creeper) is a deciduous tendril, hardy climber that is grown for its foliage. It sticks to walls using tiny sucker pads so it does not need any support and is useful to cover a large wall with the minimum of effort. It will grow in any fertile, well-drained soil in sun or shade. The plant really stands out in the autumn when it will turn a wall to flame when the leaves change to a bright red colour.
Autumn for Planting
There is an old nurseryman’s saying that ‘Autumn is for planting’. In the autumn the soil is still warm and is less likely to dry out so conditions are ideal for the roots to grow and develop. Roots will grow and spread through the winter. Next spring the plant will have developed a good root system.
The Maigue Flower and Garden will have a Christmas Worknight in Marie Shanahans – Stonehall Farm next Wednesday 3rd December. For further details contact Marie Shanahan on (061) 393362