Trees in the Garden

It is quite difficult to imagine a garden without trees or at least one tree. More than any other plant they give a sense of permanence and maturity to any garden and help to link it with other trees beyond the garden and the broader landscape. They are vital parts of any garden design in that they add height, structure and focal points as well as offering enormous variety in terms of size, shape, colour, flower, foliage, fruit and bark. They are useful for the screening of unsightly objects or views, they provide shelter and shade and they are invaluable for supporting wildlife. They, of course, come in many different sizes from dwarf and prostrate conifers to forest trees of 100 feet (30 metres) high and choosing the right ones for the garden setting can sometimes be a difficult task. Hopefully what follows will help.

The first decision needs to be made about the height and spread of the tree in relation to the size of the garden. Consulting the tree’s label or books and the internet will give some ideas about height and spread say at 10 or 20 years or at maturity. We have all seen a house and front garden dominated by a very large tree which may have seemed perfect at planting time but is now far too large for the site! For most gardens these forest or woodland trees are obviously not suitable but if you still want to grow them then you need to consider growing them as Bonsai as I do. By using this method I can grow trees such as Larch, Cedar and Beech which in their true size would quickly overwhelm our garden. Using the same principle it is also possible to grow trees in more normal sized containers and those such as many of the Japanese Maples, Star Magnolias (Magnolia stellata) and fruit trees on dwarf root stocks are particularly suitable for this.

  

A group of Acer palmatum about 30 years old and a Fagus sylvatica (Common Beech) just going into autumn colour also about 30 years old!

As I suggested in the introduction trees offer the gardener a number of attractive features which are dealt with in what follows. Especially for smaller gardens where perhaps there is only space for one or two trees it is important that each tree earns its place by bringing more than just one benefit to the garden. So as when choosing most plants it is worth looking for those that offer more than one attractive feature. One way of doing this is to choose a tree which has been created with this in mind. For example we have what is known as a “top worked” Cherry tree which has a top of Prunus ‘The Bride’ with its small, ribbed leaves which are pinkish when new, green through the summer and then orange-yellow in autumn plus in spring delicate, simple, pink flowers turning to white. This has been grafted onto a Prunus serrula (Tibetan Cherry) trunk which has beautiful, glossy, peeling copper-brown bark which you simply cannot walk past without wanting to touch.

   

Prunus serrula trunk                                 Acer palmatum  ‘Dissectum’ in a container

Once you have decided on the size of tree suitable for the garden the next feature to consider is the shape of the tree and there are a good number to choose from.  Probably the most common is the “rounded”, lollipop shape which we all drew as children, for example Sorbus aria (Whitebeam) and Malus ‘Golden Hornet’.  Another common shape, particularly amongst conifers, is the “conical” shape, another shape we can all draw! Next comes the “weeping” shape with examples including  the Weeping Willow (Salix chrysocoma), not that I would recommend this for most gardens, Betula pendula ‘Youngii’, Salix caprea ‘Kilmarnock’ and several weeping Cherries and Crab Apples. Many of these are top grafted to give an attractive weeping top on a strong trunk and rootstock. Requiring a bit more space is the “spreading” shape which are great for creating shade such as Catalpa bignoniodes (Indian Bean Tree) and Prunus ‘Shirotae’ (often named as ‘Mount Fuji’). If space is at a premium then an excellent shape for a tree is the “columnar or fastigiate” shape. These narrow trees are obviously great for the smaller garden and include Prunus ‘Amanogawa’ and Carpinus betulus ‘Fastigiata’ (Hornbeam). Finally we have the “prostrate”, ground-hugging shape, many of which are conifers such as Juniperus ‘Blue Carpet’ and Picea pungens ‘Prostrata’.

All trees have size and shape but not all have flowers or at least noticeable ones so those that do are particular favourites as garden trees. The flowers may be fleeting but they are often spectacular and memorable. Autumn, winter and spring flowers are especially valuable as they provide a display at a time when there might be less interest from other plants. Flower displays can, of course, be extended by planting climbers such as Clematis and Roses near the bases of mature trees. Some of the best flowering trees include:-

Amelanchier lamarkii, the wonderfully named Snowy Mespilus which has 5-petalled, star-shaped white or pink-flushed flowers in spring as well as bronze leaves when young and then orange-red in the autumn.

Cornus kousa (Flowering Dogwood)- each flower consist of four, large creamy-white bracts which resemble large petals, ageing to pink-tinged white in late spring. If this is not enough the flowers are followed by strawberry-like, fleshy red fruit and then in autumn, deep crimson-purple leaves.

Crataegus oxyacantha (laevigata) (Hawthorn, May)- clusters of white, pink or red flowers, single or double depending on the cultivar produced in late spring

Laburnum x waterei ‘Vossii’ (Golden Chain Tree)- long, tapering chains of yellow, pea-like flowers hang from its branches in late spring, early summer but be warned all parts are poisonous if eaten.

Magnolia stellata (Star Magnolia)- multi-petalled, star-shaped, white or pink, slightly scented flowers in early to mid-spring.

Magnolia x soulangiana (Tulip Magnolia)- large, tulip-shaped flowers ranging from white, through pink to purple depending on the cultivar in early to mid-spring.

Malus (Crab Apple)- white, pink-white or bi-coloured pink and white flowers, usually in clusters, producing a mass display in late spring eg. Malus ‘Evereste’- a dwarf, mass flowering cultivar with flowers which are pink in bud opening to white. As a bonus later fruits are red-flushed, yellow-orange and long lasting.

Prunus (Flowering Cherry)- so many different species and cultivars but most produce a profusion of single or double, white through shell-pink, mid-pink to purple-pink flowers from late to mid-spring eg. Prunus ‘Okame’ which is a delightful, round-topped, small tree with crimson-rose flowers in early spring. Some species flower even earlier such as Prunus x subhirtella ‘Autumnalis’ (Winter Flowering Cherry) which produces clusters of white or pink, cup-shaped flowers in milder periods from autumn through winter on bare twigs.

Some trees follow their flowering  with brightly coloured fruits or berries and these bring yet another dimension to the garden. Some of the best include:-

Crataegus (Hawthorn)- many species and cultivars produce red berries in the autumn, much loved by birds.

Ilex (Holly)- berries are produced from autumn onwards by female or self-fertile trees eg. Ilex x altaclerensis ‘Lawsoniana’ which needs a male tree nearby for pollination and Ilex aquifolium ‘J.C.van Tol’ which is self-fertile.

Malus (Crab Apple)- some crab apples produce larger, more useful and longer lasting fruit than others eg. Malus ‘John Downie’ produces quite large, slightly elongated, red-flushed orange fruits that can be used to make crab apple jelly. Malus x robusta ‘Red Sentinel’ is one of the best for small gardens with clusters of glossy-skinned, cherry-like fruits which are yellow-flushed red at first maturing to bright red and lasting well into the winter.

Sorbus (Rowan)- these have many, small  white flowers in late spring and early summer  but their berries are much more attractive and colourful. Particularly good ones include:-

Sorbus aucuparia (Mountain Ash)- with masses of orange-red berries much appreciated by Blackbirds and Thrushes!

Sorbus cashmiriana– blush-pink flowers in early summer produce clusters of marble-sized, white berries from autumn onwards.

Sorbus commixta– large bunches of red berries.

Sorbus ‘Joseph Rock’- one of the most popular Rowans with yellow berries, carried in drooping bundles from autumn onwards which the birds seem to leave on the tree a bit longer than red berries!

There is no doubt that trees which have attractive flowers and fruits make a big impact in any garden. However, these features are relatively fleeting when compared to the leaves of a tree and many trees are grown just for their leaf colour and shape which for deciduous trees, at least, are on the trees from spring right through to the end of autumn. In spring and summer leaves are not just ‘green’, they come in a whole range of different greens, yellows, pinks and purples  as well as some having variegations in white and cream. Some of the most attractive ones include:-

Acers (Maples)

Japanese Maples eg. Acer palmatum ‘Aureum’ and A. shirasawanum ‘Aureum- both with yellow foliage, whereas  A. palmatum ‘Trompenburg’ and ‘Garnet’ have red-purple leaves.

Larger Maples eg. A. platinoides ‘Crimson King’- deep crimsom-purple and A. platinoides ‘Drummondii’- variegated green and cream leaves.

Catalpa (Indian Bean Tree) eg. Catalpa bignoniodes ‘Aurea’- bright yellow leaves, bronze when young

Cercis canadensis ‘Forest Pansy’- bears small, deep crimson flowers in clusters on bare stems followed by heart-shaped, dark red-purple leaves.

Eucalyptus (Gum Tree)- many have blue-grey, aromatic leaves eg. Eucalyptus gunnii (Cider Gum) and E. paucifolia subsp. niphophila (Snow Gum).

Gleditsia triacanthus (Honey Locust)- golden-yellow young foliage, pale green at maturity, turning yellow again in the autumn.

Prunus (Ornamental Cherry)-eg. Prunus cerasifera ‘Nigra’ (Purple-leaved plum)- in spring the bare branches are flooded with small, pink flowers followed by  red leaves that mature to a blackish-purple and P. ‘Royal Burgandy’- pink flowers in spring with quite large, rich burgundy  leaves turning crimson-red in autumn.

Pyrus salicifolia ‘Pendula’ (Willow-leaved Weeping Pear)-a popular, small, weeping tree with branches clothed in narrow, grey, downy leaves. White flowers are followed by small, green pears which unfortunately are not edible.

Robinia pseudoacacia ‘Frisia’ (False Acacia)- has golden-yellow foliage turning yellow-green in summer, then orange-yellow in autumn.

In the above I hope I shown that some trees have really attractive leaves through the spring and summer but for many people it is the autumn leaf colour which produces the really spectacular displays and like me I hope you have started to enjoy this year’s show even though it has been a bit too wet and windy for the best displays so far this autumn. Hopefully over the next few weeks you will have the chance to admire some of the following:-

Acers- Most Maples produce good autumn colours but some of the very best are:-

Acer palmatum ‘Osakasuki’- a rounded, bushy tree with seven-lobed leaves which turn a brilliant scarlet in autumn

Acer japonicum ‘Aconitifolium’- has deeply lobed leaves turning dark red in autumn

Acer rubrum ‘October Glory’- has glossy foliage which turns brilliant red in autumn

Acer campestre (Field Maple)- has small, five-lobed leaves turning bright yellow in autumn

Acer griseum (Paper Bark Maple)- has three-lobed leaves turning orange-red in autumn

Amelanchier lamarkii (Snowy Mespilus)- not only has wonderful white flowers in spring but is also ablaze in autumn with red and orange foliage

Cercidiphyllum japonicum (Katsura Tree)- a lovely, graceful tree with heart-shaped, bronze foliage at first, changing through blue-green in summer to yellow, pink or even purple in autumn. Fallen leaves even smell of burnt sugar when crushed!

Liquidamber (Sweet Gum)- one of the very best and most reliable of the autumn-colouring trees with shining-green, maple-like leaves that turn through a range of colours from pale orange to deep red-purple which are still on the tree after most other leaves have fallen eg. L. styraciflua ‘Worplesdon’.

Parrotia persica (Persian Ironwood)- glossy, green leaves turn yellow, orange and red-purple.

Prunus– many of the ornamental Cherries produce not only spectacular spring flowers but also stunning autumn colour eg. P. sargentii– orange-red, P. subhirtella– yellow, P. ‘Okame’- orange and red, P. ‘Royal Burgundy ‘- red.

Rhus typhina (Stag’s Horn Sumach)- generally wider that tall with pinnate leaves (small leaflets along a central rib) turning brilliant orange-red in autumn.

If all of this is not enough for you I can offer you more in the form of striking bark and unusual structures! Amongst the best are:-

Acer eg A. griseum (paper Bark Maple)- famous for its peeling, papery, orange-brown bark and its three-lobed leaves turning red and orange in autumn and A. ‘Sangokaku’ (‘Senkaki’)- which has bright, coral-red shoots throughout the winter.

Betula (Birch)- Don’t dismiss the native Silver Birch (Betula pendula) with its silvery-white bark and slightly weeping structure although other Birches do have more striking bark eg. B. utilis var. jacquemontii (Himalayan Birch) with its almost pure white bark at a relatively early age and  B. albosinensis (Chinese Red Birch) with peeling, orange-brown bark, cream when newly exposed.

Eucalyptus eg. E. paucifolia subsp. niphophylla (Snow Gum)- the leathery grey-green leaves grow on glossy shoots, bloomy white when young. The bark on its main branches and trunk flakes to form a patchwork of grey, cream and green.

Prunus eg. P. serrula (Tibetan Cherry)- has mahogany-red, polished and peeling bark which just has to be touched.

Salix (Willow) eg. S. alba var. vitelline ‘Britzensis’- has bright, orange-red winter shoots. S.matsudana ‘Tortuosa’ (‘Erythroflexuosa’) (Twisted Willow)- with upright, twisted shoots giving it an outline which is particularly striking in winter and highly valued by flower arrangers.

Most of the trees that I have mentioned so far are deciduous rather than evergreen. This is because apart from conifers (not all conifers are evergreen but most are) there are not many evergreen trees which are suitable for most gardens. I think the subject of conifers for gardens deserves its own blog and I will cover this topic in the near future.

I have already written about Eucalyptus and Ilex (Holly) in this blog and other evergreen trees for gardens would include:-

Cotoneaster eg. C. cornubia is what is known as a semi-evergreen which basically means that it is evergreen in milder winters. It has white flowers in summer which in our garden attracts bees in large numbers followed by red berries which in turn are much appreciated by our Blackbirds! Another good Cotoneaster is C. ‘Exuriensis’ which has white flowers followed by yellow berries. A third evergreen/semi-evergreen Cotoneaster is C. ‘Hybridus Pendulus’ which again has white flowers and red berries.

Magnolia grandifolia– easily recognised by its large, leathery, polished leaves with big, bowl-shaped, fragrant cream flowers from late summer into autumn. It does best in a warm, sheltered site but be warned it can get quite large.

Quercus ilex (Evergreen Oak)- a popular but again large tree often used for screening or as a specimen in a large garden.

I have written this blog at this time of year because the autumn is such a good time for planting trees as well as many other types of plant. So I thought I would finish by just running through the basic processes of tree planting with apologies to those of you who have done it many times before!  Most trees that are planted these days are container grown which can be planted at any time of the year as long as the soil is not waterlogged or frozen although for various reasons the best times are autumn and spring. Bare-rooted trees are field grown and are lifted once they have dropped their leaves in the autumn and the sooner they are planted the better but at the latest by the end of February. The method of planting is basically the same and is as follows:-

• Dig a hole about 3-4 times wider than the diameter of the tree’s root ball or root spread and a little deeper than the depth of the root ball so that the roots will be encouraged to spread out giving greater stability.
• Remove any turf and weeds to avoid competition for nutrients and water.
• Loosen the soil in the sides and base of the hole with a fork.
• Mix the removed soil with some organic matter and some slow release fertiliser such as bonemeal.
• If using a single, vertical stake hammer into the hole just off centre on the windward side.
• Return some of the soil to the hole.
• Prepare the tree by giving it a good water or for a bare rooted tree a soak for 10-15 minutes. Then gently tease out the roots or in the case of bare rooted trees spread out the roots and trim any which are damaged. For container grown trees remove any weeds from the compost.
• Hold the tree in the hole to check the planting depth. It is important to plant the tree at the same depth as in the pot or in the case of a bare rooted tree just above the highest roots. Adjust by adding or removing soil as required.
• This is the time to add mycorrhizal fungi which I strongly recommend. They are not expensive and come in sachets in dry granule form. These are beneficial fungi which live on the tree roots (and other plants) and develop their own root system. They live in a symbiotic relationship with the tree and provide nutrients straight into the tree roots which basically gives the tree a double root system. The dry granules must be in contact with the roots so sprinkle them over the sides and base of the wet root ball or all over the wet roots of a bare rooted tree. Some can also be sprinkled in the base of the hole.
• Backfill the hole and firm the soil around the roots by “putting the boot in!”
• Fork over lightly and water well to settle the soil around the roots.
• If using an angled stake add at this stage, driving it in at 45 degrees leaning into the prevailing wind.
• Fasten the tree to the stake using a flexible tree tie just below the point where the lowest, substantial branches come from the trunk.
• Cut back any damaged twigs, long side shoots and any thin branches below the top of the stake. Any thicker branches can be left on to help to help strengthen the trunk and removed over the next two or three years.
• Mulch around the root area with compost or bark to help retain moisture and supress weeds.
• Stand back, admire your work and feel good about yourself!

One thing to remember though is that up to half the new trees planted each year in this country die in their first year in the ground, mainly because of a shortage of water. It is therefore vital that in dry spells during the first year the tree is given additional water. It is also important that the water gets down to the roots where it is needed so a good watering ie. at least a couple of cans perhaps once a week is much more effective than a light sprinkle every day. If you have several trees to look after it is a good idea to fit a vertical pipe near the root ball which can be watered using a hose when required.

I hope you have found at least one tree in the above that you feel you must add to your garden. Go on you know you want to! It is good for you, it is good for the garden and it is good for the environment!

I have purposefully chosen trees which are widely available in nurseries and garden centres and I know that the Old Railway Line will have topped up their tree stocks ready for the autumn. Many of their trees come from Frank Matthews, a well-respected grower from Tenbury Wells so you could say that they haven’t had to come a treemendous distance- sorry I couldn’t resist it! Why not have a look for yourselves or go on line to see what’s available if you prefer Click and Collect?

The next blog will be at the beginning of November when I will do my best to keep interest in the garden going for another month even though you might be a bit reluctant to get outside as much as you have been doing.

Until then good tree planting and keep safe.

Keith.