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Best trees for alkaline clay soil


Garden Guides | The Best Trees for High Alkaline & Hard Clay Soil

While low pH levels and clay soil often seem to go together like peanut butter and jelly, in reality many regions experience hard-packed clay that is actually alkaline rather than acidic. You can neutralize this “lime” or “chalk” soil somewhat with copious amounts of peat moss or chemicals. But it’s much easier to landscape with the many plants which thrive under both hard clay and alkaline conditions. Fortunately, several trees fall into that category, and all are hardy to zones 3 or 4.

Silver Maple

Landscapers prize the handsome silver maple for its rapid growth, graceful branch structure, delicate leaves and brilliant yellow foliage in the fall. The tree grows from 45 to 75 feet tall. Its drawbacks, according to garden writer Barbara Damrosch, include easily broken branches and an invasive root system. Damrosch recommends a careful pruning schedule in homeowners promptly remove waterspouts and spindly branches, preferably in late summer or early fall. The tree likes a sunny location with moist soil.

Hackberry

A good choice for erosion control and shade, hackberry thrives where few trees will. Growing as tall as 60 feet, the hackberry grows anywhere from Canada to Texas. Town planners often use it to line streets because of its ability to withstand pollution and drought. It will grow under the shade of other trees, preferring stream beds and other moist places. The U.S. Department of Agriculture admits that while landscapers don’t count the tree as the country’s handsomest, hackberry usually withstands fungal and insect infestations without succumbing to them. The tree bears smallish fruit which, while not fit for human consumption, attracts birds and other wildlife.

Green Ash

Green ash grows quickly to its ultimate height of 40 to 60 feet--much shorter than other ash trees. The green ash shares many features with its bigger brothers, however, including a preference for sunny, moist growing conditions. When pruning and training the tree, encourage a single trunk and remove weak-looking branches.

Australian Pine

Although once used extensively for erosion control on American beaches, the Australian pine grows so vigorously that some states now consider it invasive. Check with your extension service before planting it. The dark evergreen tree grows at least 50 feet high and spreads 20 to 30 feet wide. As its former use suggests, Australian pine tolerates salt, wind and other tough conditions, including unusually wet or dry conditions. It grows well in sun or partial shade.

Bur Oak

Noted for its graceful, spreading silhouette, the bur oak can grow as tall as 100 feet, although 60 feet is more common. The tree can tolerate neglect and drought, and its deeply-ridged bark and branches offer winter interest, as do its draping, yellowish catkins. The long-lived bur oak also bears unusually large acorns.

Honeylocust

Honeylocusts are small but mighty. Although growing only 30 to 60 feet tall, honeylocusts reach that height quickly. Obtain a thornless variety, if possible, and plant it in a sunny, moist location. The hardy tree provides dappled shade and features yellow foliage in the fall.

Best trees for clay soil: 11 varieties for every garden

Knowing the best trees for clay soil is important if you have heavy, clay soil in your garden. Having this type of soil can be a big challenge when it comes to gardening as it is hard to work and has poor drainage which can prevent many plants from thriving. Clay soil also warms slower than sandy soils – and can be hard for roots to penetrate. 

If you're looking to bring height, structure and year-round interest to your garden ideas then trees are a brilliant addition which will make a lasting feature decades to come and there are plenty of beautiful options available suited to clay soils – we've gathered a selection below with help from some of the experts. 

Best trees for clay soil

Despite these drawbacks, clay soils are often nutrient rich and can be advantageous to certain kinds of plants and trees.

‘Clay soils hold an ample supply of moisture which makes them perfect for some trees and shrubs that require high moisture tables to thrive,’ explains Tammy Sons, CEO of Tennessee Nursery . 

1. Crab apple 

(Image credit: Getty Images / whitemay)

The crab apple or 'Malus' is one of the best trees to grow in clay soils as it offers interest throughout the year – and is also a great pollinator. In spring, this beautiful tree is covered in a profusion of white blossom with green foliage in summer. 

In fall, they bear fruits which are beautifully decorative and can range from glossy red to pink-flushed orange to yellow. Due to its high levels of pectin – most commonly used to thicken jams, jellies, and preserves – the fruits are often used to make Malus ‘Jelly King'.

They are compact trees only growing to a mature height and spread of  around 13ft, so are perfect for smaller gardens. They thrive in full sun with moist soil that is well-drained. 

Fruit trees require a fertile, nutrient rich soil that retains moisture, so they are best matched to heavy clay soils. Whilst some have the tendency to be tricky to work with, clay soils are highly beneficial when it comes to producing thriving fruit trees,' explains Marcus Eyles, horticultural director of Dobbies . 

2. Alder

(Image credit: getty Images / annick vanderschelden photography)

Alder – or Alnus glutinosa – grow vigorously in cool, wet conditions and are often found by rivers and lakes making them a good choice for sites with poor drainage.  

‘In the Pacific Northwest where there is clay soil, we also usually have drainage issues due to all of the rain we get here. A good choice for these types of environments, rain and clay soils, are Alders,’ says Lisa Tadewaldt of Urban Forest Professionals .

‘Two great choices are White Alder Alnus rhombifolia or Red Alder Alnus rubra. The toughness of these trees is really the primary reason to plant them.’

Alders have racquet-shaped, leathery dark green leaves with serrated edges and put on a beautiful display of catkins between February and April. Alders are monoecious so have both male and female catkins on the same tree. The female catkins turn into tiny cones during the fall season. 

3. Sorbus Commixta 

(Image credit: Leonie Lambert / Alamy )

Sorbus, also known as Japanese Rowan trees, are a brilliant choice for fall color due to their ash-like foliage which turns from green to a dazzling array of orange and red.  They also have blossom flowers in spring, and fruit in fall, so therefore offer plenty of ornamental interest throughout the year.  

Growing to around 25-40ft, Sorbus are deciduous trees which are hardy in the UK and can be grown in North America in zones 5-9. They require pruning in the dormant season to create a strong structure to support their fruit. 

4. Birch

(Image credit: Anna Stowe Botanica / Alamy )

Birch trees or betula are beloved for their snowy white peeling bark which makes a beautiful feature during the winter months, as well as their elegant form and attractive foliage which turns from mid-green to yellow in fall. 

‘This tree can grow in a variety of conditions and is tolerant of heavy moisture, meaning it’s ideal for soils with high clay,’ says Marcus Eyles, horticultural director at Dobbies .

Betula utilis jacquemontii or the 'Snow Queen' birch is a slender specimen which will grow to around 22ft tall making it a good choice for small garden ideas. Plus, this specimen requires minimal pruning.

5. Cornus Kousa 

(Image credit: Getty Images)

Also known as Japanese Dogwood, this abundant semi-evergreen tree offers year-round interest with flowers, fruits – and beautiful red leaves in fall. Come June, it features four-petalled creamy white flower bracts which turn pink over time and come fall it bears pink strawberry-like fruits. 

It can be planted in all soils but prefers a position that is moist but well-drained in full sun or part shade. It is suited to growing zones 5-8. 

6. Magnolia x Soulangeana 

(Image credit: Nigel Cattlin / Alamy)

A spring show-stopper, this deciduous tree, also known as the Saucer or Chinese Magnolia, has large tulip-shaped flowers in late spring, these are white with a pink tinge at the base and can be scented. Its obovate leaves are glossy green, but they start of red in spring before turning to yellow in fall. 

The Saucer Magnolia grows to a height of 20ft–30ft tall with a 25ft spread and prefers moist but well-drained soil. In North America it is suitable for growing zones 4-9.  

Heavy pruning can cause shock; remove damaged or overcrowded branches or prune to shape in late summer early fall. 

7.

Amelanchier 

(Image credit: Getty Images / Massimiliano Finzi )

Also known as the Snowy Mespilus, or Juneberry tree, the Amelanchier is a good, hardy tree for growing in poor conditions.

‘The amelanchier is a great tree for clay soil and is known for its clusters of white blooms in spring and splendid fall color,’ advises Marcus Eyles, horticultural director at Dobbies . ‘This tree thrives in moist soil so is perfect for planting in heavier, clay soils that take longer to warm up, and will add drama and interest to your garden year-round.’

Offering plenty of interest from season to season, Amelanchier has bronze tinged foliage in spring, turning to green in summer and to orange-red in fall, it also bears a star-shaped flowers in spring followed by berries that ripen in summer and turn from dark red to purple black. 

It can tolerate part shade but will flower best in full sun. Amelanchier needs minimal pruning; damaged and criss-crossing branches can be removed in fall or early spring. It will reach a mature height and spread of 15-25ft.

8. Japanese Red Maple 

(Image credit: Marianne Majerus)

Japanese maples – or acer palmatum – are small deciduous trees that bring magnificent fall color. They make brilliant specimen trees planted singularly and are slow growing, reaching mature heights of 15–25ft with a spread of around 20ft, making them a good choice for your courtyard garden ideas. 

They prefer a sheltered spot – and variegated varieties will need partial shade as full sun can scorch the leaves. They are hardy in Europe and in North America are suited to growing zones 5-8. 

9. Holly

(Image credit: Getty Images/ Danielle D. Hughson)

‘If you’re looking to add a touch of festive greenery to your garden with clay soil, consider trees like the Crataegus, known as the Hawthorn, or the Ilex, more commonly known as the Holly tree,’ suggests Marcus Eyles, horticultural director at Dobbies . 

‘These seasonal trees will add warmth to your winter garden ideas with their ruby red berries, and they are tolerant of heavy moisture, making them ideal for clay soils. ’

The glossy evergreen leaves of hollies will bring color year-round; for added interest consider variegated varieties such as 'Golden King' which has an RHS Award of Garden Merit. Another benefit of Hollies is that they are able to tolerate exposed, coastal sites – provided they have ample sun. Size can vary between varieties so be sure to do your research.

10. Cotoneaster

(Image credit: Alamy / Avalon.Red)

Cotoneasters range from ground cover plants to wall or border shrubs through to larger trees with long weeping branches with a dome-like habit such as 'Cotoneaster x Watereri' or 'Cornubia' which can grow to around 18ft. 

Cotoneasters will provide year-round interest and are an excellent choice for wildlife gardens. Their dark leaves are great foil to clusters of white spring blossom which keeps the bees and insects happy, while their copious berries are a good source of food for birds throughout fall and winter. Berries can range in color from yellow through to red and purple.  

One of the advantages of Cotoneaster trees is that they can tolerate any soil type and can be grown in all positions, even in rough, coastal areas. They are fully hardy in Europe and in America and are suited to growing zones 6A-9B. Pruning is not required but they can tolerate harsh pruning if reshaping is needed.

11. Laburnum

(Image credit: Getty Images / Pietro triglia )

Also known as the ‘Golden Chain’ tree due to its beautiful trails of golden yellow flowers, Laburnum is a small deciduous tree that can be grown alone or trained around arbors. 

Fantastically, it is quick growing and low maintenance as it does not require pruning. You can simply tidy it up and remove damaged branches during the dormant period. Laburnums will flower better in full sun but can tolerate some shade and will not do well in the heat or waterlogged soils.  They are hardy in the UK and are suited to USDA planting zones 5-7.

Be area that Laburnum is highly toxic to humans and animal. We recommend that you do not plant this variety near children and pets – and gloves should be worn when handling.

Planting trees in clay soil

When planting trees in clay soil there are some steps you can take in order to help them establish.

'Horbeam, hawthorn and birch are medium to large trees well suited for heavy clay soils. That being said, no newly planted tree will thrive in waterlogged conditions therefore it’s essential to prepare the tree pit carefully,’ says landscape designer Henry Scott of Pehrsson Scott . 

‘Breaking and forking the base of the pit will allow the roots to penetrate the soil and adding a good amount of grit to the base of it will mitigate against water pooling.’

You can also look to improving the soil prior to planting, as Marcus Eyles, horticultural director of Dobbies explains.

‘To get the most out of your clay soil use a peat free mature plant compost (John Innes No. 3) and mulch with Bloomin Amazing, or Dobbies peat-free soil improver. When planting with heavier clay soils add horticultural grit to the base of the planting hole to help open up the soil and improve drainage.'

What to plant on clay soil

When landscaping and developing a site, we often encounter soil imperfections. The clay composition of the soil leads many gardeners and gardeners to despair and despair. Clay soil is very difficult to work and unsuitable for planting a huge number of plants. The earth has a very dense structure: it does not let water through, it is poorly ventilated, it freezes in winter and does not warm up well in summer. Heavy soil is mostly clay and contains a small amount of sand. If organic matter gets into the soil, then the lack of air does not allow the decomposition process to take place actively. After rains, a hard crust forms on the surface of the clay soil, which blocks the access of oxygen, thus, it gradually dries up and becomes unsuitable for planting.

Clay soil, structure determination

A small test will help you determine the type of soil. A small amount of soil, wet it, and roll a small sausage in your hands. When dry, cracks in the sausage will indicate loamy soil, the absence of cracks will indicate clay soil. The clay type of soil has little or no structure at all. During the rainy season, it is not amenable to processing and loosening. The constant lack of water or its excess negatively affects the growth and development of plants. The acidity of clay soil can be different.

  1. Acidic soil occurs in places where there is very high humidity. In such a place grows sedge, horsetail, plantain.
  2. Nettle and quinoa grow on neutral soil.
  3. Alkaline soil is dense and has a high salt content. Mullein, wormwood, and yarrow often grow on such soil.

Thus, knowing the characteristics of the soil in your area, you can adjust its structure and improve its composition. This is of course a very time-consuming and costly procedure, the result of which will be a stable, high-quality crop and an abundance of crops grown on it.

Fruit trees and berry bushes growing on clay soil

When choosing plantings, be sure to consider what type of clay soil you have. Clay soil is not as hopeless as it might seem at first. With the improvement of the soil structure, it is possible to plant seedlings of some moisture-loving, fruit trees.

  1. Apple, chokeberry, pear, plum, quince, cherry, fig, hawthorn grow well and yield richly on clay soil with good drainage. To do this, the soil from the planting pits is removed and changed to a nutrient soil mixture. Drainage is laid in the planting pits. A special nutrient composition is being prepared, consisting of peat, humus, sand, tree bark and garden soil.
  2. Berry bushes: currants, blackberries, raspberries - can grow and delight with an abundance of harvest when organics are added to clay soil. To create favorable conditions, apply 15 kg of organic fertilizer per square meter. If desired, humus and peat can be added to the topsoil, such a composition is favorable for growing strawberries and strawberries.

Ornamental trees and flower crops that prefer clay soil

Many types of trees love clay soil, plant ornamental plum, viburnum, Norway maple, gray alder, willow, oak. Unpretentious, moisture-loving plants will help make the site more attractive.

Flower crops that grow well in clay soils can bring life to an otherwise unsightly area. Violets, roses, lilies, verge, phloxes grow very well on clay, and with proper fertilization, delightful, abundantly flowering flower beds and flower beds grow. Irises, marigolds, petunias, peonies, geraniums, tradescantia tolerate dense clay soil well. Anemones, coreopsis, forget-me-nots, and hostas thrive in moist, heavy soil.

You may not be limited to planting only this group of plants. Add nutritious soil to clay soil, then it will be possible to grow many exotic, ornamental plants. When planting such plants, rotted humus is added to the planting pits. The structure of the land is improving and it becomes possible to grow barberry, spirea, mock orange, astilbe Arends, pink alcea.

Important! To grow vegetables in clay soil, you need to add 0.5-1 bucket of sand and 0.5 bucket of humus for each square meter when digging. Such soil is suitable for growing cabbages, beets, beans, peas, potatoes, peonies and some varieties of roses.

Improvement of the soil structure with fertilizers

You can not limit yourself to applying fertilizers to the hole, but to carry out a fundamental change in the composition of the soil throughout the clay area. To improve the quality of the soil, it is necessary to carry out a number of preparatory measures.

  1. Level the area, there will be stagnant water in the lowlands and irregularities, make drains or bends.
  2. Before the onset of frost, dig the clay area without breaking large lumps.
  3. In the spring this area needs to be dug up again. Clay soil on the site can only be improved by adding fertilizers. The most commonly used compost, peat, humus, manure. When digging the soil in the spring, add fertilizer and lime. Fertilizer makes the soil loose, and lime will remove acidity. For each square meter, add 1-2 buckets of humus or peat.

When using manure, be careful, fresh manure will not be able to improve the quality of the soil, because the decomposition processes in the clay do not occur, try to apply only well-rotted manure.

If the soil is very heavy and difficult to cultivate, you can add finely crushed brick and crushed bark.

Modifying clay soil with sawdust

Sawdust helps to make clay soil loose and breathable. Sawdust is added when digging up the site at the rate of 1 bucket per square meter. It is better to use sawdust used for bedding for livestock, they will not pull nitrogen out of the soil when they rot. If this is not possible, then take sawdust moistened with a 1.5% urea solution. They will increase the flow of air and will not reduce the fertile qualities of clay soil.

Increasing soil fertility with green manure plants

Green manure plants enrich the soil with nitrogen, phosphorus, calcium, magnesium and loosen the soil. The uniqueness of plants is that they can increase the fertility of a large area without significant costs. When growing green manure in one place for about 3 years, the soil structure improves significantly and becomes suitable for the growth of many vegetable crops. Some plants can be sown for a short time, during this period the soil receives nutrition and breathability.

  1. Alfalfa can be used as a fodder plant. Powerful roots grow to a depth of 3 meters, they loosen the soil and enrich it with phosphorus and nitrogen.
  2. Peas are often planted as a separate planting, or together with potatoes, under trees. Growing peas has a fruitful effect on heavy soil types, the plant saturates the soil with nitrogen, phosphorus and organic matter.
  3. Sweet clover copes well with nematodes and actively accumulates nitrogen in the soil. The quality of the soil after the growth of sweet clover is actively improving.
  4. Buckwheat has a deep, branched root system, growing, it loosens the clay soil and accumulates nitrogen, saturates it with fluorine and calcium.
  5. White mustard has the ability to suppress weeds, and also contributes to the destruction of the wireworm. Mustard roots grow in the ground to a depth of 1 meter. The soil is not only enriched, but also loosened, receives an additional supply of oxygen. Mustard is recommended to be sown on clay soils, a month before planting potatoes. After cutting the green mass, the roots rot in just 10-15 days.
  6. Meadow clover is a good nitrogen enricher. The plant can grow well near trees and around shrubs.

After harvest, rye or phacelia can be sown in the garden. These plants will perfectly cope with loosening the soil, significantly improve its composition.

Clay, heavy soil * not a sentence. Try to use the most suitable way for you to enrich your site with an abundance of ornamental, fruit and vegetable crops. You can choose plants that love clay soils, or you can change the soil structure yourself and make it more fertile and suitable for growing exotic plants. Any site can be transformed and become picturesque!

Which trees and shrubs can be planted in clay soil? Photo - Botanichka

Some gardeners are afraid to plant something in clay soil, and they can be understood. Such soils retain too much water, especially in autumn and spring, and dry out too much in summer. However, a large number of plants adapt perfectly to this type of heavy and suffocating soil. Having clay soil doesn't mean you can't have healthy fruit trees that produce good crops.

What trees and shrubs can be planted in clay soil?

Clay soil has a number of unpleasant properties. This soil expands and sticks together depending on how wet it is. In addition, clay soil is prone to compaction and warms up slowly. These are difficult conditions to which not all fruit plants can adapt. Fortunately, some types of fruit and nut trees are able to live in clay soil. Let's look at what fruit and nut trees can be planted in clay soil.

What to plant in clay soil? The best fruit trees and shrubs:

1.

Apple tree in clay soil

Europe's most cultivated fruit tree, the apple tree (Malus domestica) is a win-win for clay soils. Apple trees have a huge selection of varieties, shapes (columnar, erect, sprawling, etc.) and growth strength (from 1 m to over 10 m in height). In addition to giving us fruits, the apple tree is an excellent ornamental tree in the spring when it is in bloom. This tree also provides food and shelter for all the beneficial fauna in the garden.

This fruit tree requires full sun and dense, clayey, rich but well-drained soil. The apple tree is much more resistant to limestone and late frost than the pear tree.

The apple tree needs a sunny location and dense, clayey, rich but well-drained soil

What you need to know about growing apple trees in our article: Apple orchard - important questions and answers

2. Pear in clay soil

More one timeless classic. The pear (Pyrus communis), like the apple tree, is found in almost every garden. There are many varieties, some prefer temperate climates, while others grow best in the south.
Beautiful pear blossoms, earlier than apple and can sometimes be caught by late spring frosts. It should also be noted that pear yields are always higher with cross-pollination. Remember to plant several different varieties that have the same flowering time.

Pear loves dense, clayey, rich and fresh and well-drained soils. If your clay soil is too heavy and dense, choose a quince-grafted pear tree. Pears grafted onto wild pear rootstocks do best in calcareous and drier soils.

Pear loves dense, clay, rich and fresh and well-drained soils

See also our article: Growing pear - planting, care, pruning, varieties

3. Plum in clay soil

Plum trees (Prunus domestica) and plum trees mirabelle type (Prunus domestica subsp. syriaca) grow well in clay soil. Plum trees tend to be small in size, and the spring bloom of many small white flowers looks absolutely beautiful.

Plum loves very sunny places, protected from strong winds that break branches. It is a vigorous tree that grows in all soils, preferring rich, deep and clayey soils that are fresh but well drained, with a slightly acidic pH, without stagnant moisture or too much lime.

Plum loves very sunny places, protected from strong winds that break branches. It is a vigorous tree that grows in all soils, preferring rich, deep and clay soils

Read our article: Plum in detail. Cultivation, useful properties and variety selection

4. Hazel (hazel) in clay soil

Common hazelnut (Corylus avellana) is also a valuable fruit tree that can grow on clay soil. There are both decorative and fruit varieties, so you need to choose a variety that has a high yield and produces large fruits.

Hazel is also an interesting tree or shrub because of its long, hanging catkins that bloom in late winter or early spring. Some varieties also have decorative purple foliage. This shrub is very suitable for the edge of the garden to form a beautiful free-growing hedge.

Hazelnuts are very hardy and very easy to grow, they grow well in sun or partial shade, in any type of soil, even clay, provided it is relatively well drained and not too dry.

Hazelnuts are very hardy and very easy to grow, they grow well in sun or partial shade, on any type of soil, even clay soil

5. Peach in clay soil

Peaches are deciduous trees that grow up to 3- 4 meters high. They have oblong foliage and beautiful pale pink flowers. These trees prefer well-drained soil. However, their specific requirements vary by variety. In particular, the Redhaven peach is an easy-to-grow variety that requires little maintenance. This variety is tolerant of clay and sandy soils as long as there is good drainage. This peach is hardy for USDA hardiness zones 5 to 9..

Peach in clay soil

6. Cherry plum in clay soil

Cherry plum is a large shrub or small tree. It can reach a height of 3 to 6 meters. This tree blooms very early and produces edible fruit from July to September, with a sweet to sour taste.

This tree will adapt to clay soils provided they have good drainage. You need to plant cherry plum in places that receive full sun. Unfortunately, cherry plum is a problem for some animals. It can be toxic to cats, dogs and horses. Some parts of it are also poisonous to humans, as the stems, leaves, and seeds contain cyanide. It is also a short lived tree. Cherry plum usually lives only up to 20 years.

Cherry plum adapts to clay soils if they have good drainage

How to grow cherry plum? Find out in our article: Growing cherry plum according to the rules

7. Mulberry in clay soil

Mulberry is a deciduous tree that produces small, tasty fruits similar to raspberries in summer. Mulberry trees are easy to grow, but not suitable for every garden. It is important to keep in mind that they are very prolific and have fast growing roots. Plant this tree away from important structures such as foundations, a driveway or garage, septic tanks or sewer lines so you don't risk the roots damaging your important property.

You must also take into account the tree's mature height and choose a location where it can be kept relatively free from pruning (which stresses it).

Mulberry trees are highly adaptable and can easily handle clay, loam and sandy soils as long as the soil can support adequate drainage. Trees will thrive in a neutral to moderately acid pH range.

Mulberry trees are highly adaptable and can easily cope with clay, loam and sandy soil if the soil can support sufficient drainage

How to prepare clay soil for fruit and nut trees?

One of the most important things for these trees to grow well is well-drained soil. Unfortunately, clay soil is made up of tiny particles that make it difficult for water to pass through, causing the ground to remain saturated with moisture for a long time.

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