Traditionally, until the early 1960’s, nurseries grew their plants in the field then lifted and sold them during the winter as bare-rooted and root-balled plants. Container grown plants were introduced to prolong the planting season into late spring and early summer.

Plants will start to shut down for the winter, like most sensible hibernating animals, and begin their dormant stage. The growth shoots cease to grow and there is little or no water loss at this time of the year; water loss is the biggest cause of failure at other times of the year. Deciduous plants will have a natural surge of root growth once their leaves have dropped hence autumn to spring being the optimum time to plant.

Evergreen plants will shed leaves a few at a time, continuously throughout the year. Therefore, remember that in winter they will have some water loss but it is still the right time to plant or move them. They may need watering-in when planted if the weather conditions remain dry.

Get ready with your winter protection before the frosts arrive and do the damage. Winter containers should be made of a frost-proof material, traditionally clay, stone or wood but now modern materials such as zinc and resin are available, all in various shapes and sizes. Whatever container is chosen, for the good of the plant there needs to be adequate drainage in the bottom by putting in a layer of ‘crocks’ or pebbles before the compost. It will also help the plants by raising the containers off the ground by using pot feet.

More exotic plants such as olives and trachycarpus (palms) will survive in Britain in pots but the drainage needs to be good. It is not the low temperatures on the foliage which causes the problems, as my Italian counterparts tell me, as even in Pistoia (the plant growing region of Italy) the temperature drops to -10°C in winter! The problems start when the soil becomes wet and the roots freeze.

Enjoy the autumn colours before the leaves fall off for winter. Autumn colours do seem to be a hit or miss affair from one year to the next but either way there will be gold at the end of the rainbow as summer draws to a close. Every autumn the daylight hours diminish, temperatures fall and the green leaves turn into a delight of yellow, orange, red and purple shades as a result of the transformations in leaf pigments. Seasonal changes on the nursery are always highlights for us especially in the autumn. It is also a great time for customers to get a feel for autumn interest at our nursery in North Aston.

Here is a brief guide to the chemistry surrounding the change in leaf colour. Back to basics first: the green pigment on the leaf is chlorophyll, this absorbs red and blue light from the sunlight which falls on the leaves. It is not a very stable compound so plants require a large amount of sunlight and warm temperatures in order for the synthesis of chlorophyll in plants. During the summer, chlorophyll is continuously broken down and regenerated in the leaves of trees and the leaf stays green.

The second pigment is carotene which absorbs blue-green and blue light; the light reflected from carotene appears yellow. When chlorophyll and carotene work together the light reflected by the leaf appears green. However, carotene is a much more stable compound than chlorophyll so the shortening days and cool nights trigger a change in trees. The flow of nutrients into the leaf is interrupted and the production of chlorophyll declines and the green colour of the leaf fades. Trees like birch contain carotene in their leaf so the leaves will fade from green to bright yellow.

Now a third class of pigments come into play called anthocyanins. These absorb blue, blue-green and green light so the light reflected appears red. Unlike chlorophyll and carotene, anthocyanins are not attached to cell membranes but are dissolved in the cell sap and are affected by the increase in the concentration of sugars and the ph in that sap. This is why Acers get a better autumn colour if they are grown on more acidic soils.

The green leaves will turn red and purple as in the red maples, red oaks and sumach. The range and intensity of autumn colours is greatly influenced by the weather. A general statement is that the brightest autumn colours are produced when dry, sunny days are followed by cool, dry nights.

Trees to plant if you want to achieve a yellow autumn leaf colour are:

• Birch
• Field maple
• Hornbeam
• Tulip Tree (‘Liriodendron’)

Orange leaves can be seen from

• Beech
• Nyssa (‘Tupelo’)
• Smoke bush (‘Cotinus’)

Finally the fiery reds are produced from:

• Spindle
• Amelanchier
• Specific varieties of maples, red oak, sumac and . . .
• My favourite the Sweet Gum (‘Liquidambar’)

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