Gardening Advice

Protecting your box hedges from attacks

 

An essential feature of French-style gardens, box hedges are ideal for marking out the borders of a flower bed or kitchen garden. At Villandry, our kitchen garden is bordered by seven kilometres of small box shrubs. The variety used is the Buxus sempervirens ‘Suffruticosa’ – or dwarf box. The advantage of these plants is that they grow slowly and only need to be trimmed once a year, in April. From the Buxacaea family, these shrubs can survive for several centuries. Originating from the Mediterranean, they are at home in dry, limestone soils with good drainage, but also happily grow in cool soils in mid-shade. Over the last few years, new diseases have started to appear on these small shrubs.

It is a combined attack of two fungi specific to box plants: Cylindrocladium buxicola and Volutella buxi. They are more commonly known as: Box Blight. This recent disease in Europe was described in the UK in 1994, where it is quite widespread, then in New Zealand in 1998 and in Belgium in 2000. It started to crop up in other European countries including Switzerland and now France since 2007.
Its symptoms include:
Cylindrocladium buxicola: This fungus attacks the box leaves and stems. Light marks form on the young leaves, encircled by reddish-brown colouring Darker marks which fuse together as the disease develops then form on the older leaves. The leaves will finally become completely dry and fall off.

After being infected by Volutella buxi, yellowish or darker marks will appear on the upper surface of the leaves. The dark-green hue of the leaves will lighten and the leave will become brittle and fall off. If humidity is high, fruiting bodies producing reddish spores will clump together on the lower face of the leaves. Highly infected branches can wither completely.

One of the varieties of box most sensitive to these attacks is the one found at Villandry, Buxus sempervirens ‘Suffruticosa’. We recommend you avoid planting this shrub and instead replace it with the Buxus sempervirens arborescens if you absolutely want to have box trees growing in your garden. There are other precautions to take to keep your box trees healthy: Avoid watering the bushes with a sprinkler system as this keeps the leaves moist; aerate the shrubs; do not trim them too often; remove infected branches and collect the fallen leaves from the ground. These measures are difficult to follow for box hedges or for shrubs which have been carefully shaped into balls.

Importantly, avoid the excessive use of fertilisers; a plant that is too well fed is more sensitive to disease. At Villandry, we do not supply our box trees which border our beds with a particular fertiliser, we simply fertilise the flowers and vegetables in the beds and the shrub roots also benefit.

Here is the fertilisation plan for our garden:

  • 15 March: 50 grams/m² with 9-3-3 fertiliser
  • 25 April: 50 grams/m² of 7-3-12 fertiliser
  • 15 June: 50 grams/m² of 7-3-12 fertiliser
  • 5 August: 50 grams/m² with 9-3-3 fertiliser

We use the Eco mix range of fertilisers made by DCM, authorised for use in organic farming.
There are chemical treatments available on the market which are authorised for use in gardens and cover a whole range of cryptogamic diseases. For instance Octave which if applied four times a year can achieve a preventive effect.

At Villandry, we do not use any synthetic chemical products. We have put in place a prevention plan that includes different forms of copper, an authorised product in organic farming:

Winter:

  • 21 November Copper hydroxide 400 ml / 100 l
  • 20 January Copper hydroxide 400 ml / 100 l
  • 10 March: Copper hydroxide 400 ml / 100 l
  • Spring: 1 application after pruning
  • 26 April Bordeaux mixture (copper sulphate) 1.5 kg / 100 l

Summer: 1 or 2 applications according to rainfall

  • 12 July Copper hydroxide 400 ml / 100 l
  • 17 August Bordeaux mixture (copper sulphate) 1.5 kg / 100 l

This plan is not set in stone; it can change depending on any contamination that may occur and the weather. The repeated use of copper can also become toxic when it accumulates in the soil. In 2012, despite the wet conditions, the treatments managed to reduce the disease identified in June.

Gardening should always be a pleasure. To keep your garden and shrubs looking lovely, the best solution is to keep a regular eye on the health of your plants. After all, this just gives you another excuse to spend more time in the garden!

Laurent Portuguez
head gardener 

The lime trees in the Villandry gardens

The lime trees in the Villandry gardens

The virtues of the lime tree have been known since the Middle Ages. They are planted near hospitals, purify the air and have a calming effect when taken as a herbal infusion. The lime is a ...

Woolly apple aphid

Woolly apple aphid

Looking at the apple cordons planted in our kitchen garden, once the leaves have fallen, we have sometimes discovered whole branches covered with a blanket of cotton as white as snow. Colonies of ...

Hornbeam hedges

Hornbeam hedges

Our French formal gardens are made up of clipped plants that form an architectural structure all year round. In addition to box shrubs and yews, hornbeams became a favourite of 17th century ...

Prune to prevent the rose plant

Prune to prevent the rose plant

Prune to prevent the rose plant from losing its lower leaves and to renew the shoots so as to ensure exceptional blooms all year round. March is the best time of year to prune rose plants, ...

The main enemy, the common garden snail

The main enemy, the common garden snail

Slugs and snails have the same purpose: to devour seedlings, soft leaves, and sometimes fruits and roots. Their gluttony takes place mostly at night and in wet weather; at Villandry, the damage ...

Apple scab

Apple scab

Spring has barely started, but it’s already time to think about the late summer and autumn harvests. To ensure we can enjoy apples and pears picked fresh from the tree, we have to keep a watchful ...

Spring cabbage… and the cabbage fly

Spring cabbage… and the cabbage fly

We starting sowing spring cabbage in our heated greenhouses on 7 February 2012. Two varieties this year, starting with ‘Précoce de Louviers, a traditional variety with an elongated pointed head. ...

Mowing the lawns

Mowing the lawns

Spring is finding it hard to settle in this year: the rain and the cold temperatures are preventing us from enjoying the gardens as we would like. Leaf growth is late, and the vegetables in the ...

The yew topiary at Villandry

The yew topiary at Villandry

When the gardens at the Château de Villandry were created, Joachim Carvallo planted yews (taxus baccata) in order to form topiary according to the French tradition. 162 yews were distributed ...

Roses, Black spot

Roses, Black spot

This disease is caused by a fungus called Marssonina (or diplocarpon) rosae; the symptoms appear quickly starting with black spots on the leaves, followed by yellowing and finally premature leaf ...

Eco-friendly garden

Eco-friendly garden

Villandry Castle, symbol of French style gardens, today shows that carefully maintaining an outstanding garden can be compatible with eco-friendly methods. At the end of 2008, we decided to stop ...

The orange trees

The orange trees

Villandry respects the tradition of the great châteaux by placing 10 clementine trees at the foot of its tower in Versailles planters. The fashion for citrus dates back to the fifteenth and ...