Olive trees, or Olea europaea are generally considered the kings of the Mediterranean landscape, but popularity in the UK has increased in recent years. This fact sheet will tell you how to grow Olive trees successfully in the UK.
Their combination of gnarled stems and tough silvery grey-green leaves provide handsome evergreen structure to gardens. They flower in the Summer and can grow up to 10m (30ft) in height, but respond well to pruning.
Olive trees are adaptable and hardy plants suitable for growing in a wide range of climates. In the UK, olive trees perform well in milder climates which tend to be in southern and western regions, coastal areas and urban locations. Due to the short summer in the UK it is unusual to expect trees to produce olives.
To ensure you give your olive tree the best possible start in life, here are some tips:
Choosing a site – Position in the sunniest site possible, ideally south or west facing with some protection from the north and east winds. Olives will tolerate some shade but want at least half a day of sun.
Ground conditions – Ensure planting soil is free-draining that will not become waterlogged during winter; olives are tolerant of both acidic and alkaline soils. Poor sandy soils will benefit from the addition of soil improver or compost and clay soils may require additional grit. Raised beds are an ideal way of raising the roots away from waterlogged soils.
In containers – Olive trees can successfully grow in containers for many years. We recommend mixing a good quality multi-purpose compost 50/50 with John Innes No.3, or buy our ready mixed ‘Multi Purpose with added John Innes’. Never over-pot your olive tree and always re-pot just to a slightly larger container. Make sure that pots have good drainage holes and that the bottom of all containers are filled with some drainage crocks (pieces of broken terracotta pot). Line the inside of pots with bubble wrap to protect roots from winter frost if you live in a cold area or a frost pocket.
Watering – Older olive trees can tolerate quite prolonged periods without water. Plants in smaller pots prefer little water often and can put up with drying out between waterings.
Pruning – Olive trees respond well to pruning to maintain the size and habit required. Light, formative pruning maybe undertaken in mid-spring once the plants are in growth, with heavier trimming in early to mid-summer. Avoid pruning in autumn and winter as olives need some heat and recovery time to heal wounds before the dormant winter period. Olives produce ‘suckers’ – growth of small shoots from the base of the trunk and up the trunk. These are best removed to encourage the plant to put its energy into the crown of the plant. Thinning the crown of the tree to avoid branches rubbing and making sure you can see daylight between branches will encourage healthy growth.
Feeding – Feed your olive trees with ‘Miracle-Gro All Purpose Slow Release’ plant food in spring. If your plant has lost leaves in winter and you want to give it a boost, apply ‘Maxicrop Complete Garden Feed’ fortnightly between May and August to ensure the tree stays healthy, vigorous and happy.
Cold weather – It is very hard to be prescriptive about the hardiness of olives. As a guide, older olives planted in free-draining soil will tolerate the lowest temperatures. An old potted olive planted in the middle of Patrick’s Patch since 2009 has survived temperatures of -15ºC over a few nights. Olives without gnarled stems in areas where the minimum winter temperatures are between -2°C and -5°C require no winter protection and will even tolerate drops down to -7°C for short periods, providing the daytime temperature rises sufficiently. In areas of lower winter temperatures, your olive tree can be protected with several layers of horticultural fleece wrapped around the trunk and crown of the tree.
Like many plants grown in pots, olive trees have not yet evolved to tolerate frozen roots. If this happens, they can suffer drought through inability to take up water or, worse still, the roots will be damaged which can result in subsequent poor growth or even death of the tree. But fear not, this can be prevented by adding several layers of bubble plastic to the inside of the pot when re-potting the plant or simply add layers of bubble plastic to the outside of the pot and secure with string.
Delivery – We can deliver small olives in our regular van. Providing only 2 members of staff are required to deliver the trees our standard delivery terms apply. Where an additional member of staff is required an additional £25 is charged within our normal delivery area.
Larger olives require specialist delivery equipment, which we can access at cost to the customer. If you require your olive to be planted or potted we can provide a quote from our Landscapes department – please contact 01590 612307 for more information.