Hollies are beautiful, glossy evergreen trees that provide seasonal interest in the garden. The small clusters of white flowers bloom from early spring to summer. These can transform into the infamous, vibrant red holly berries that will litter the branches in autumn and keep a pop of colour in the garden through the bleakest winters reminding us that Christmas is only round the corner.
Our Holly Tree Care Guide aims to bring you all the latest advice and tips so you can take the best care of your tree. Follow our expert recommendations to find out how to look after your holly trees.
Quick Facts:
- Variety: Ilex aquifolium
- Hardiness: Hardy
- Suitable for: Planting in the ground and container growing outdoors
- Height: up to 12m (40ft) if left unpruned
- Flowering: Spring and Early Summer
- Fruiting: Autumn
- Soil: Tolerant of most soils, slightly acidic
- Sunlight: Partial shade to full sun
- Difficulty: Easy, Low Maintenance
How to Care for Holly Trees
Choosing the Location for your Holly Tree
Holly trees aren’t that fussy when it comes to choosing a planting spot in your garden. They are a tolerant variety and will do well in most locations, from partial shade to full sun and accepting of most soil types as long as it’s not waterlogged.
When it comes down to it though, they do prefer a well-draining, slightly acidic soil type so choosing an area in the garden that can provide this will do the tree a world of good.
The tree can grow well in an area of partial shade but it will thrive in full sun which will ensure you get the best looking holly with plenty of flowers and bright red berries.
Holly is great for both planting in the ground and growing in a container, follow the steps below for both.
Planting your Holly Tree
Once you’ve chosen the perfect location, it’s time to start planting. The best time for this is either spring or autumn giving the tree enough time to establish before any extreme winter or summer weather. Plus, if you plant your holly tree in spring, it will give it more than enough time to start working on those vibrant berries.
To prepare for planting you will need to dig a hole that is larger than the rootball. Remove the tree from its current pot by loosening the soil around the edges and pulling it out by the base of the main stem.
Place the tree in the hole and fill in with surrounding soil, ordinary garden soil should be fine but if you wish to add any compost we would recommend using some Johns Innes no. 3.
Once the tree is planted, water it 3-4 times a week for the first couple of weeks. Once the tree has become more established it shouldn’t need watering very often.
Pot Growing Holly Trees
Due to the slow-growing nature of holly trees, this makes them perfect for planting in a pot.
However, be wary that holly can grow up to 12m (40ft) in height so it might be best to go for a dwarfing holly variety if you do want to keep it in a container.
Choosing a container:
Make sure to choose a size that is able to accommodate the size of your growing tree. You will also need to ensure you choose a pot with adequate drainage as one thing hollies are not tolerant of is soggy roots.
How to Repot:
- The soil should be slightly moist when repotting, if it’s too wet then leave it dry slightly, too dry then give it a little bit of water.
- Hold the tree by the base of the main stem, loosen the soil around the edges of the pot and remove the tree.
- Add some extra soil into the bottom of the new pot before you insert the plant. We recommend John Innes number 3. 10-20% of horticultural grit or perlite can be added to improve drainage.
- Fill in around the plant with the mix of soil, compost and grit
- To allow the roots to bed in, keep the plant well watered for several weeks, we recommend watering every couple of days.
Container grown trees should be repotted every couple of years until it has reached its final height. Over time, the tree will deplete the nutrients in the soil of the pot which makes it important to either replace 50% of the compost or repotting the tree every few years.
Watering your Holly Tree
Young and recently planted trees will require regular watering until they have had time to become established.
When your holly tree has become established in the garden it should require very little maintenance in regards to watering. Rainfall should do the tree just fine with a little top up here and there in times of drought and hot spells of weather.
Trees in pots do require a little bit more attention when it comes to watering as their soil dries out much quicker, especially in hot weather. To check the moisture levels, feel the first couple of inches of topsoil. If it is dry to the touch then give the pot a good water.
Mulching the area around the base of trees that are both planted and in pots will help keep the moisture locked in the soil for longer. This can be in the form of wood chips or another organic matter.
The amount of watering should be reduced in winter when conditions are colder and wetter.
Feeding / Fertilizing your Holly Tree
The best time to feed your holly tree is throughout spring or autumn. They like either a well-rotted manure, garden compost or a broadleaf evergreen fertiliser.
To fertilise using manure or compost, simply spread it along the surface of the soil that covers the root zone, this will penetrate down to the roots over time. If you choose to use the fertiliser, this should be used per instructions on the packet as usage will vary by brand.
How and when to Prune a Holly Tree
If you holly tree is young (under 2-3 years) pruning should be avoided where possible. When it does become time to prune, holly responds very well and can be pruned back quite vigorously without having a negative impact.
To prune a branch or stem, always make sure to cut back to a growing bud, this will encourage the tree to send out new shoots and leaves which will, in turn, create a more full and bushy tree or plant. The tree can be pruned to any shape or size you wish following this advice.
Any leaves that have been cut through this process can turn slightly discoloured at the edges so we recommend carefully pruning back to avoid the cutting of any leaves.
If you are choosing to prune your tree to a particular shape then remove any branches that are not uniform or are ruining the silhouette. This will help keep it nice and tidy looking
As a protocol, always remove any dead or diseased branches to make sure the growth of the tree is not affected by these. It is also a good idea to prune away any crossing branches at the centre of the tree to ensure there is enough space for light and air to get right to the middle.
Make sure not to prune too close to winter as the new growth that will occur will not be hardened against any cold weather or frost.
Left unpruned and they can grow to giant heights of 12m (40ft) and more.
Why have the leaves on my Holly Tree turned yellow?
The 2 main causes of yellowing leaves on holly trees are either waterlogged soil or an iron deficiency. If the soil is very wet then this may indicate that you are over watering or the soil needs its drainage improving.
There are a couple of ways to improve the drainage of the soil, just follow the tips below.
- Add well-rotted organic matter to the soil about once a year this will help keep the soil aerated which will also improve the drainage. Garden compost or manure will work for this.
- Coarse grit can also be added to the soil to improve this issue.
These tips can also be applied to any pot-grown trees.
More often than not the iron deficiency is also caused by the soil being too wet as this can pull the iron from the roots and leach any important nutrients. This deficiency is called iron chlorosis, and due to the lack of iron, the tree stops producing enough chlorophyll which is why they lose the deep, emerald colouring.
If you improve the drainage of the soil and see no improvement in the colour of the leaves the soil could be generally low in its iron content or the pH could be too high (alkaline) adding fertilisers with a more acidic content or trace amounts of iron should help bring the tree back to it’s usual healthy self.
Why isn’t your Holly Tree Producing any Berries?
Most holly varieties are dioecious meaning that the plants are either male or female. Only female plants are able to produce the berries, however, they need a male tree nearby for pollination. Without this, they will never produce berries.
To identify whether your holly tree is male or female you can check the flowers in the spring. They may look very similar to each other but male trees will produce flowers with more prominent stamens.
When it came to the naming of different holly varieties it can make it a little more confusing as many of the names can imply the opposite. For example, the Golden King Holly is actually a female variety.
Only one male holly tree is needed in close proximity to pollinate several other females.
If your tree does produce some berries, make sure not to eat them as they can cause mild stomach upset. These will provide food for wildlife in the garden when everything else has become scarce.
Holly Tree Winter Protection
Your holly tree should be quite happy to fend through the winter without much protection. Just make sure that it’s not too exposed and protect it from any strong winds that could tear or puncture the leaves when they are blown together.
Holly Varieties
Our Holly Sapling is an Ilex aquifolium variety - native to the British Isles, our little holly tree makes a wonderful Christmas gift. The leaves are the deep, glossy green that gives holly its well-known reputation.
The Handsworth New Silver Holly has variegated leaves, the deep emerald centre outlined by a crisp white outer layer - this tree makes for an unusual Silver 25th Wedding Anniversary Gift. The new silver holly is a male tree and can be used to pollinate other female holly trees.
The Golden King Holly Tree also has beautiful variegated leaves, with the outline a lovely yellow colour. This evergreen beauty would make a great Golden 50th Anniversary Gift. Golden King tree is a female variety and will produce dark red berries when pollinated.
