Jorge, Plants

Soil types, such as clay, sand and silt, are compositions of different size rock particles, which affects a soil’s nutrient and water holding capacity and drainage. They aren’t as important as made out as every plant will adapt to its conditions and every soil type is improved the same way – through maintaining plant life and adding organic matter. 

What are soil types?

When people are talking about soil types, they are usually referring to soil texture. A soil’s texture is determined by the composition of rock particles in the soil. These particles come in different sizes, and the smallest are known as the fine earth fraction, which range from the largest sand (.05-2mm) to the smallest clay (<.002mm) with silt (.002-05mm) in the middle. 

Within clay are very small particles (0.0001mm) known as colloids. Colloids have the ability to absorb, hold and release nutrients and are important as without nutrients would simply leech away. This occurs as they are negatively charged and attract positively charged ions such as nutrient atoms and water molecules, which bind to the surface. Hence, as particle size decreases, water and nutrient holding capacity increases. 

particle composition of soil types
Picture credit: Mikenorton (2011) licensed under CC BY-SA 3.0.

From this, we arrive at the different properties each soil texture possess. Clay and silt are rich in nutrients and have good water holding capacity, but drain poorly, and are vulnerable to being waterlogged. Sand is poor in nutrients and water holding capacity, but drains quickly. Loam famously has the best properties of any texture. 

Soil is composed, not just of rock, but decomposed organic matter known as humus. Silt and sand particles are bound to clay and humus particles forming peds (aggregates). All soil types benefit from adding organic matter and maintaining plant life. 

soil peds type

In clay soils, adding organic matter acts to increase aggregate size, decreasing the amount of macropores, improving drainage. In sand, adding organic matter acts to increase the amount of micropores, improving the water holding capacity. This is because organic particles can also be very small (colloids) but are even more chemically reactive. 

So how does organic matter improve silt and loam soils? Organic matter provides feed for plants and soil organisms that act to increase the porosity of the soil and break down minerals into soluble forms. 

Chalk and peat soils are slightly different. Chalk soils can be made up of different particles sizes, but are notable for being alkaline. Peat soils are heavily organic and are often acidic. 

Are soil types important?

Soil types aren’t as important as made out as every plant will adapt to its conditions. Most plants are planted/seed in suboptimal conditions and provide good results. More important is how you look after the plant, such as whether you water, fertilise and apply mulch. Planting is critically important. Avoid compacting the soil or otherwise a soil’s porosity will be reduced. 

Now, it’s important to avoid waterlogged soils, which act to starve a plant of oxygen, causing root rot, and eventually root death. pH is also important. Camellia, rhododendrons, and blueberries will not do well in neutral or alkali soils, so are best grown in pots. 

What’s the best soil for pots? 

Using a mix of garden soil and compost will produce the best mix of macropores and micropores. Again, care is key. Potted plants are especially liable to drought, so be sure to apply mulch, which helps trap moisture. Ensure you drill a hole in the bottom of the pot, so water can drain. 

Jorge at PrimroseJorge works in the Primrose marketing team. He is an avid reader, although struggles to stick to one topic!

His ideal afternoon would involve a long walk, before settling down for scones.

Jorge is a journeyman gardener with experience in growing crops.

See all of Jorge’s posts.

Flowers, Jorge, Plants, Trees

bee pollination

Pollination involves the transfer of pollen from one flower to another, resulting in fertilisation. Fertilisation is important as without plants will not produce fruit. It’s likely you don’t need to do anything to ensure pollination, as it’s probable a compatible tree will be in the vicinity. However, it is beneficial to buy a pollination partner to guarantee and improve pollination, boosting yields. 

What is pollination?

Pollination involves the transfer of male reproductive cells from a plant’s male reproductive organ to a plant’s female reproductive organ, in within there are female reproductive cells. The reproductive cells then fuse, forming a new cell, which divides rapidly eventually forming a seed. 

In plants, male reproductive cells are located within pollen cells, which are found on flowers, on the part known as the stamen. The female cells are located within the ovule, found in the ovary, which is part of the carpel. Often, both the male and female reproductive organs are found on the same flower – such flowers are known as perfect flowers – but sometimes they are not. Sometimes, male and female reproductive organs are found on different trees, known as male and female trees.

flower parts

The male reproductive cells must be compatible with female reproductive cells or otherwise fertilisation will be inhibited. Fertilisation can be inhibited if two varieties are too closely related or too distantly related. Some varieties – known as self-fertile plants – can fertilise themselves, while others – known as self-sterile plants – can’t, and therefore need to be partnered with another variety. 

As pollination is sexual reproduction, resultant offspring necessarily contain information from both male and female reproductive cells. Therefore, the seeds of any fruit will be of a different variety than that of the parent. (This is true even in the case of self-fertilisation, because of genetic recombination and Mendel’s law of segregation.)

Most plants, including most fruit trees, rely on insects, primarily bees, to transfer pollen between flowers, but some rely on the wind. 

walnut flowers
The male and female flowers of a walnut. Walnuts rely on the wind for pollination. Picture credit: Dalgial licensed under CC BY-SA 3.0.

What we are interested in is not fertilisation, but the production of fruit, which unfortunately, most trees will not bear without fertilisation. This is because fleshy fruit develops from the ovary, which encloses the ovules that form seeds.

Do I have to worry about pollination?

If you live in an urban area, it’s probable there will be another compatible tree in the vicinity, and as bees forage for miles, there is a high chance of pollination. If you live in an isolated location, where you can’t be certain of another compatible tree, it might be best to buy a pollination partner.

Now, just because you live in an urban area, it doesn’t mean there is no benefit to buying a pollination partner, which will not only guarantee pollination, but help improve pollination. You can tell if a plant has been poorly pollinated, if it’s fruits are small, misshapen and have few seeds.

Low temperatures impede pollination as frost can damage blossoms, which will fail to turn into fruit. Early flowering stone fruits, such as almonds and apricots, are especially vulnerable, and the former will not reliably crop in the UK. As bees will not forage when it is cold or windy, bad weather impedes pollination also.

fruit trees flowering timeline

As pollination is primarily carried out by bees, it’s necessary that insects can access your flowers. It’s also necessary that two varieties flower in the same period. Hence, why trees are put into flowering groups, with any variety being able to pollinate another in +-1 flowering group. Flowering groups are preferred to specific dates, as plants will flower at different times in different parts of the country. A variety in flowering group 1 will always flower before a variety in flowering group 2.

apple pollination groups

pear pollination groups

cherry pollination groups

Unfortunately, even if a plant is in the same flowering group, it doesn’t mean pollination is guaranteed, due to genetic incompatibility. Cherries are notorious for this, so it’s always best to buy a self-fertile variety. Triploids, such as Bramley, are sterile and are unable to pollinate other species. So, if you want a triploid, it’s necessary to partner with two non-triploid varieties. 

Different species can sometimes pollinate one another. Famously, crabapples can pollinate apples, and are often used as part of an orchard to help with pollination. Ornamental cherries, however, can’t pollinate cherry fruit trees. 

cherry and apple pollination compatibility diagram

Jorge at PrimroseJorge works in the Primrose marketing team. He is an avid reader, although struggles to stick to one topic!

His ideal afternoon would involve a long walk, before settling down for scones.

Jorge is a journeyman gardener with experience in growing crops.

See all of Jorge’s posts.

Jorge, Plants, Trees

If crabapple trees had an alternative name it should be the utility tree, as you get unmatched value from a single tree. Lately, it’s been common to straightjacket trees as either ornamental or fruiting, but crabapples excel at both, producing wonderful floriferous displays and versatile fruit, great for cooking and attracting wildlife.

What are crabapples and how do they differ from apples?

Crabapples grow throughout the Northern Hemisphere, including in North America. Most species’ fruits are less than 2 inches in diameter, but there are some exceptions to this such as Malus sieversii, the progenitor of the modern apple whose fruits are as large as 7cm.

Sieversii grows on the slopes of the Tien Shan mountain range on Kazakhstan-China border, but once grew widely, stretching all the way to Almaty – the ex-capital of Kazakhstan that derives its name from “fatherland of the apple”. In these wild apple forests, the fruits are eaten by bears, which act to disperse and fertilise the tree’s seeds.

Here, fruits can be as small as 2.5cm, which shows the powerful selection effect humans exerted. Many are sour and are unsuitable as eating apples and there is a wide variety of flavours including hazelnut, liquorice, sweet honey and berries.

Crabapple fruits are significantly smaller than apple.

Sieversii spread wherever humans travelled, and were a great portable snack, and useful feed for horses. Eventually, it was crossed with Malus sylvestris, the European crabapple, which is native to the UK, and is commonly grown in hedgerows.

Sieversii and sylvestris and to a lesser extent some other crabapple species gave us the apple, Malus domestica. Therefore, it is correct to say all other Malus species that are not domestica are crabapples, even if crabapples and apples are closely related and can crossbreed.

Even today, growers are attempting to introduce genes from sieversii and other crabapples into domestica as they naturally resistant to disease.

Why buy crabapple trees?

Unlike other trees, crabapples produce multiple bursts of colour in a year with nearly every flower turning into a sizeable fruit, which often completely cover the crown. One particularly heavy fruiting variety, ‘Golden Hornet’ literally lights up with a mass of warm golden-yellow fruits.

‘Golden Hornet’

Often the colour of the bud is different than the emerging flower, and as the buds open at different times, every bloom is multi-tone. With ‘Sun Rival’, the bud is pink-red and the flowers white.

The warm tones crabapples produces when it’s leaves begin to colour up are not given justice, with different varieties turning yellow, orange-red and maroon. ‘Prairie Fire’ spectacular autumn shades is arguably match the best maples and sweet gums.

Unlike the other blossom tree, the ornamental cherry, whose evanescence blossom symbolises the transient nature of beauty, crabapple blossom lasts for weeks, as they flower on both one-year wood and spurs. With the variety ‘Profusion’, flowering lasts for a whole month.

The extended flowering time makes crabapples ideal for attracting pollinators to your garden as well as pollinating your apples. Indeed crabapples are in a class of their own when it comes to apple pollination, and are commonly used by commercial growers in orchards.

They suffer from none of the genetic incompatibility issues apple do (some are too closely related) and can pollinate apples spread across multiple flowering groups. If you are to choose a crabapple for apple pollination, it’s best to choose one with blossom that matches the colour of apple blossom, which is white with a hint of pink. This is because bees tend to move between trees with the same colour blossom.

‘Evereste’ remains the cultivar of choice for apple pollination, not just because of the colour of its blossom, but because it is resistant to apple scab, powdery mildew and importantly, fire blight. It also sits in flowering group 3 and will therefore pollinate most apple varieties.

‘Evereste’

Much like the rowan’s berries, some crabapple fruits hang on all the way until Christmas. Try ‘Evereste’, which was not named after the mountain, but is a play on the words, “forever resting on the tree”. ‘Comtesse de Paris’ is a great alternative, with its small citrus-like fruits. These fruits can help attract birds into your garden in the colder months, providing a welcome source of nutrients.

Crabapples over 4cm tend to fall off soon after ripening. With more flesh, these fruits are best turned into culinary delights. ‘Jelly King’ doesn’t follow convention with huge, pectin-rich fruits that persist longer than most large fruited varieties. ‘Laura’ makes a great alternative and is nice and compact. Both exhibit good disease resistance.

crabapple jelly king
‘Jelly King’

Crabapples can be used as part of your cider blend to raise the acidity and sugar content. This is useful as most cider apples will need to be paired with an additional tree, as any blend without requisite acidity will spoil.

Now, nearly all crabapples are too tart to be eaten raw, although eating quality will improve in time, as sugar converts to starch. One notable exception, ‘John Downie’ is good to eat when fully ripe, but doesn’t compare to the best dessert apples.

One advantage of crabapples is there small stature, which is well suited to urban planting. With most varieties reaching 5-6m tall, they are much more easily manageable than many popular landscape trees such as Acer, Birch and Willow.

Like apples, they are compatible with dwarfing rootstocks and some varieties can be planted in containers. ‘Sun Rival’ is a lovely weeping specimen with white blossom and bright red fruits that is great as a centrepiece in a small garden.

The Best Crabapple Varieties

The Dark Crabapples

Clockwise from left: ‘Toringo Aros’, ‘Toringo Aros’, ‘Toringo Scarlett’, ‘Royalty’

‘Royalty’, ‘Toringo Scarlett’, ‘Toringo Aros’ and ‘Crimson Cascade’ are all examples of crabapples with dark leaves and red, purple, pink flowers and red berries. Both ‘Royalty’ and ‘Toringo Scarlett’ have a spreading habit, and ‘Royalty’ is slightly larger. ‘Toringo Scarlett’ is small in stature and slender, making it ideal for small gardens. While its berries are almost black, it’s flowers are pink with white veins. ‘Crimson Cascade’ makes a nice alternative to the other weeping crabapple ‘Sun Rival’.

The Light Crabapples

Clockwise from left: ‘Comtesse de Paris’, ‘Admiration’, ‘John Downie’, ‘Red Sentinel’, ‘Red Obelisk’. ‘Golden Hornet’

The angelic cousins of the dark crabapples, these trees reflect light and are best used as centrepieces. Compact and naturally dwarfing, ‘Admiration’ produces possibly the best flowering display of any crabapple with its dense blooms of white. ‘Red Obelisk’ is an excellent alternative, with slightly darker leaves and deep pink buds.

‘Golden Hornet’, ‘Butterball’, ‘John Downie’ and ‘Comtesse de Paris’ all produce white flowers, followed by yellow/orange fruits. ‘Butterball’ can probably be considered an advance over ‘Golden Hornet’, as its fruits don’t rot on trees. Not previously mentioned, ‘Red Sentinel’ remains a classic with its ruby-red jewel-like fruits that hang on well into winter.

Crabapple FAQ

Are crabapples related to apples?

Crabapples are all species within the genus Malus that are not apples (M. domestica). Apples are produced from multiple crabapple species and exist thanks to human cultivation.

Can you eat crab apples off the tree?

Yes, but they’ll be tart. Crabapples are best cooked or used as part of a cider blend.

Where do crabapple trees grow?

Crabapples are found throughout the temperate regions of the Northern Hemisphere, and are therefore well suited to the UK’s climate.

How big do crabapple trees get?

Most crabapples will reach an ultimate height of between five to eight metres, but there are of course naturally dwarfing varieties and giantitic 12m varieties.

A tree’s habit affects a tree’s spread with upright trees taking up less space than a spreading tree at the same height.

Like apples, crabapples can be grafted onto rootstocks, which help reduce vigour.

You can always prune a tree to reduce its size. In orchards, growers may head a crabapple to reduce its size.

How do you identify a crabapple tree?

Most crabapples have five lobed blossom just like apples, but while apple blossom is white with hints of pink, crabapple blossom can be red, pink and pure white. Crabapple fruits are smaller than apples, being less than 2 inches in diameter, and can be yellow, red, green, purple, and pink.

The native Malus sylvestris has is lopsided, rounded crown and a wide, dense canopy. Bark is grey, and with age, often twisted and covered in lichen.

Are crab apples poisonous to dogs?

Crabapples and apples can be fed to dogs, but need to be cored as the seeds contain cyanide.

Do crabapple trees have deep roots?

Crabapples are not known to have invasive root systems. As with all trees, a tree’s root system grows horizontally as opposed to vertically as most nutrients are found in the uppermost layers of soil.

Can you grow crabapple trees in pots?

Crabapple trees can be grown in pots. Pots act to restrict growth, reducing a tree’s eventual size. With trees in pots, it’s necessary to water regularly and replenish its nutrients periodically.

Do crabapple trees need a pollinator?

Nearly all fruiting plants need to be pollinated to produce fruit. Usually this is done by insects, which transfer pollen from one flower to another. With self-fertile varieties, pollen from the same tree can be used, but with self-sterile varieties pollen from another variety is necessary. Crabapples are relatively common, and are compatible with apples, so pollination is almost guaranteed.

Can you transplant a crabapple tree?

You can transplant any tree, but chance of success diminishes with maturity.

When can you trim crabapple trees?

Crabapples can be pruned late autumn and early spring. Remove dead, dying and deceased wood and suckers and water sprouts.

Why are crab apples called crab apples?

Ostensibly, from the Swedish skrabba, meaning fruit of the wild apple tree. Alternatively, from the noun crabbed, meaning crooked or wayward gait of a crab. Crabapples are often slightly lopped sided and their fruit disagreeable when eaten fresh.

What are some good crab apple trees for small gardens?

Crowned best in show at the National Plant Awards, ‘Toringo Aros’ is one the smallest crabapples thanks to its slender habit and short stature, but also one of the most impactful with its gorgeous burgundy leaves, pretty pink blossom and dark maroon fruits.

toringo aros
‘Toringo Aros’

A worthy alternative, ‘Red Obelisk’ creates an unmatched spring spectacle with its heavily-blossomed upright branches racing towards the sky.

One of the few weeping crabapples commercially available, ‘Sun Rival’ makes an excellent choice for a centerpiece with white flowers and bright red fruit.

What is the best crab apple tree for jelly?

Try ‘Jelly King’.

What is the best crabapple tree for wildlife?

All crabapples make an excellent choice for a wildlife tree. Most and produced from a mix of species.

What season do crab apple flower and fruit?

Crabapples flower in April and May and fruit from August to October.

Small crabapples tend to hang onto the tree for longer, while larger ones fall off soon after ripening. ‘Evereste’ fruits last until Christmas.

Crabapples make excellent pollinators due to the spread of bloom. ‘Profusion’ flowers for a whole month.

Can crabapples be grown as part of a hedge?

Malus sylvestris is commonly grown as part of a mixed hedge, owing to its dense, twiggy nature and due to the fact it supports over 90 species of bird and insect.

How do I prevent crabapple tree fungus?

As fungus thrives in warm, damp and dark conditions, it’s important to remove plants that shade, crowd or grow into your tree. Trim in early spring to allow light to enter the interior and improve air circulation. Ensure sprinklers do not wet leaves and ensure you pick up dead leaves as potential sources of vectors.

If you are still considering a crabapple tree, ‘Golden Hornet’, ‘Liset’, M. floribunda and Adirondack all exhibit high resistance.

Jorge at PrimroseJorge works in the Primrose marketing team. He is an avid reader, although struggles to stick to one topic!

His ideal afternoon would involve a long walk, before settling down for scones.

Jorge is a journeyman gardener with experience in growing crops.

See all of Jorge’s posts.

Bulbs, How To, Jorge, Planting, Plants

To plant bulbs successfully, it’s important to plant at the right time and depth with the bulb the right way up. You can ensure showstopper blooms by fertilising when planting, and as long as there is vegetative growth in the growing season. Applying mulch in winter will help protect spring-flowering bulbs from frost injury. 

When To Plant

If ordering online, plant as soon as you receive the bulb, or store in a dry, dark location if you can’t plant immediately. Leave a bulb unplanted and it may fail to flower or flower poorly. If you forget to plant, examine by touch, and discard soft or rotten bulbs. Others are worth a shot. 

Generally, spring flowering bulbs need to be planted by the end of September, which will allow time for the bulb to root before the ground freezes. Tulips are planted in October and November, depending on whether you are in the North or South respectively, which helps reduce problems with disease. 

Hardy summer flowering bulbs are to be planted in September and October, while tender summer flowering bulbs in early spring. Autumn flowering bulbs need to be planted by late summer. 

BulbSeasonPlanting depthPlanting distance between bulbsPosition
AlliumAutumn10cm (4″)10cm (4″)Full sun
BegoniaSpring1cm (1/2″)30cm (12″)Full sun, semi shade, dappled shade
CrocusAutumn10cm (4″)7cm (3″)Full sun, semi shade
DaffodilAutumn10cm (4″)10cm (4″)Full sun, semi shade
DahliaSpring15cm (6″)45cm (18″)Full sun
BluebellSpring/Autumn10cm (4″)10cm (4″)Dappled shade
GladiolusSpring10cm (4″)15cm (6″)Full sun
HyacinthAutumn10cm (4″)8cm (3″)Full sun, semi shade
Iris reticulataAutumn10cm (4″)8cm (3″)Full sun
LilyAutumn20cm (8″)15cm (6″)Full sun, semi shade
NarcissusAutumn10cm (4″)10cm (4″)Full sun, semi shade
PonerorchisSpring2.5cm (1″)7cm (3″)Dappled shade
RanunculusAutumn8cm (3″)25cm (10″)Full sun
SnowdropSpring/Autumn10cm (4″)10cm (4″)Dappled shade
Tree LilyAutumn20cm (8″)15cm (6″)Full sun, semi shade
TulipAutumn15cm (6″)13cm (5″)Full sun
White Egret OrchidSpring2.5cm (1″)7cm (3″)Dappled shade
Winter AconiteAutumn5cm (2″)5cm (2″)Full sun, semi shade, dappled shade

Position 

As always it’s best to look at a species habitat and flowering time when deciding where to plant. Early spring bulbs such as snowdrops are used to harsh conditions, and will thrive in cold pockets. Forest dwelling species such as the bluebell are used to dappled shade, and will thrive under any deciduous tree. More exotic species such as dahlia, originating from Mexico, are suited to full sun. 

It’s not the end of the world if you plant in a sub-optimal location as bulbs are a storage organ and the plant already has a large reserve of energy. Bulbs rarely thrive in deep shade and output will be poor in the second year after planting. 

It’s possible that southern exposure can lead to early emergence and freezing injury. You can moderate temperature extremes by applying 3 inches of mulch after the first frost. This will help prevent injury from the constant cycle of frost and thaw. Remove the mulch if you think the shoots can’t penetrate it easily. 

Mulch will help protect bulbs from frost injury.

Soil Type

The key message is to avoid waterlogged soils, which can starve a bulb of oxygen, causing them to rot. Clay soils usually have poor drainage, and can be improved by adding organic mulch. Ensure you don’t compact the soil, but firm with the back of a rake. 

Right-side Up 

Most bulbs have a tip, which should be pointing upwards when planted. Some will arrive with roots on the bottom, opposite to the tip. Begonia bulbs do not have a sharp point, but you can sometimes detect the tip emerging out of the concave (indented) side.

Planting Depth & Distance

A general rule of thumb is that bulbs can be planted three times their height, although begonias are an exception to this. 

Bulbs in containers can be spaced a bulb width apart. In the ground, 2-4 inches is common for small and 8 inches for large bulbs. 

Apply phosphorus when planting as it doesn’t travel well in the soil. This essential nutrient helps with root growth. 

Aftercare

Water immediately after planting, unless you are planting in autumn and the ground is already wet. 

Sometimes, small mammals will dig up bulbs, but this can be prevented with wire mesh. 

Plants in containers are vulnerable to drought and under fertilisation, so water and feed regularly once the growing season starts. 

As nutrients are absorbed through roots, it’s important nutrients reach the depth the roots are located. Liquid fertiliser will penetrate the soil, and can remedy deficiencies quickly, but is liable to leeching. Other inorganic fertilisers will fertilise the soil over time, so need to be applied in advance. Organic fertiliser takes far longer as it’s insoluble and first needs to be broken down by microorganisms, before becoming available for uptake by plants. 

Removing seed pods, but maintaining foliage, allows a plant to put more energy into its bulb, for larger blooms thereafter. Watering and feeding will help with this. Remove foliage once it yellows. 

After this, bulbs can be lifted, sorted, washed, left to dry and then stored in a cool, dry, airy place. Small, rotten or diseased bulbs are best thrown. 

Jorge at PrimroseJorge works in the Primrose marketing team. He is an avid reader, although struggles to stick to one topic!

His ideal afternoon would involve a long walk, before settling down for scones.

Jorge is a journeyman gardener with experience in growing crops.

See all of Jorge’s posts.