Hazelnuts and Cobnuts - how to plant and grow them

Hazelnuts (often known as Cobnuts) are an excellent source of protein and healthy fats, and hazelnut trees are an easy and valuable addition to any orchard. They will grow successfully in most temperate situations, but nut production is likely to be better in sheltered areas.

Pollination

Pollination of hazelnuts is complicated! However there are some simple rules when planting hazelnut trees:

  • Always plant at least two different varieties, which are known to pollinate each other
  • If you have wild hazel bushes nearby, they will also act as pollinators
Cosford catkinsCosford catkins

Hazels bear male catkins and small, less conspicuous, red-tipped female flowers separately on the same tree, so have the potential to be self-fertile. However the respective flowering times usually do not overlap, so they should be considered self-sterile. This is what makes it difficult to establish suitable pollinators with hazels, since it is quite possible for one variety to pollinate another but not be pollinated in return. (This is very different to the situation with, say, apples or plums, where if cross-pollination is possible at all, it usually works both ways).

Hazels flower in winter and early spring. Pollination is carried out by the wind and is effective up to a distance of about 50m. It is quite easy to see the clouds of pollen being blown off the catkins on the breeze on an early spring morning.

As noted above, wild hazel trees or bushes are good pollinators if they are near enough for wind pollination.

The ideal pollination partner will have male and female flowering periods which co-incide with the alternate female and male flowering periods of your chosen variety so that each will pollinate the other and itself be pollinated in turn. Obviously if you plant additional different varieties pollination opportunities are further improved.

Table of hazelnut pollination compatibility.

Growth habit and planting pattern

Hazels naturally grow as multi-stemmed bushes and can provide useful screening or shelter for other areas of the garden. If you require a hedge plant new trees roughly 2m apart, depending on the variety and how dense you want the hedge.

Commercially the trend is towards open-centre trees with a single main stem. This approach allows more light to penetrate the tree which in turn improves the quality and quantity of nuts.

If you want to layout your hazel orchard in a regular planting pattern then allow about 2.5m - 3m between trees in the row and 4m - 5m between rows. The wider spacings would be for more vigorous varieties on more fertile soils. Since hazels are wind-pollinated it is a good idea to plant a mix of different varieties - either in the row or in alternate rows.

Photo of a hazel bush as supplied

Hazel trees as supplied

Most of our hazels are supplied as 2-year bushes and should start to produce nuts 2-3 years after planting - at which point they will be 2m or more in height. Vigorous varieties will eventually achieve a height of 3m or more, lower vigour varieties will be between 2m-3m.

All our hazels are currently un-grafted plants, produced by layering (i.e. on their own roots). This is a more difficult process than grafting (on Corylus avellana or Corylus maxima rootstocks), but means that the natural suckers which are common to all hazels are of the same variety as the parent plant, so if you allow the plant to revert to a multi-stemmed bush, you will still have nuts of the correct variety. In contrast, root suckers from grafted plants will be of the rootstock species and will produce inferior nuts - but will be very difficult to spot.

Young hazel trees are attractive to rabbits and other rodents. If this is a problem in your area you should protect the new trees with chicken wire.

We can also supply native British hazel hedging plants.