Autumn: the ideal planting time
Picture the scene early next year: at long last, the first day that really feels like spring. There is only only one thing on our minds: to buy new plants! We zigzag through the aisles of the garden centre planteria with our trolley. What is likely to confront us are pots with healthy, yet dormant plant material – especially for the perennials. Foliage and flowers may also be hard to find on the trees and shrubs too. Plant labels and posters shout out with the promise of colourful wonders later in the year – but not just yet.
Can this scenario be different?
Yes, and quite easily too. For many people today, their gardening activity follows a pattern of busy in spring, enjoy in summer, start to ‘put the garden to bed’ in autumn, then rest in winter in readiness for next spring. But autumn can be the perfect opportunity to invest for a fantastic, exciting, colourful garden for the coming year. Now is the ideal moment to take action. If you go to work at this time, you are guaranteed a garden full of strong, established plants next spring. So you make your own promise today and make this an autumn to plant.
Did you know that planting in autumn confers a real growth advantage over plants that you buy in the spring? Nowadays virtually the entire range of garden plants is container grown or at least sold in pots. Theoretically this frees the gardener from planting only when the plants are dormant (approximately October to March, depending on your region). But even though it’s perfectly possible to plant virtually year-round, there are several biological facts that continue to make autumn king in terms of when to plant.
If you could look closely at a plant’s root system, you would see that around the periphery of the main root network there is a complex system of fine root hairs that are essential in the uptake of water and nutrients. Planting in autumn allows these roots to spread and establish right through the winter (as long as there is no frost in the ground). As soon as the temperature starts to rise in spring, the new plant is ready to start absorbing water and food immediately – and growing.
And these are not the only advantages of planting in the autumn. The soil is often more easily worked: not too dry, not too hard, which makes for easier gardening. Trees and shrubs that come with a root ball will take root quickly if the soil is still warm. Remember that even if the air is getting cooler with the onset of autumn, the soil temperature is slower to drop. In spring the opposite applies – the air temperature can be shooting up but the soil lags behind! Planting in autumn is also likely to reduce water stress on new plants as autumn and winter rains will ensure they are much better watered in than you can achieve with a can or hose. Again, in terms of water, if your soil is clay or heavy and difficult to work when wet, planting in autumn avoids the frustration of waiting until it dries out sufficiently in spring.
The bare root advantage
Some plants, such as hedging plants, some trees and roses, continue to be offered as bare root material. The first thing to do when you buy these is to soak the roots and then plant as soon as you can, lifting the plants straight from a bucket of water and into their planting holes. Watering by you is kept to a minimum as the rain does it for you! Also, a lot of watering we do in the garden is to compensate for evapotranspiration through the leaves, exacerbated in windy or hot conditions. When the plant has shed its leaves and is barely growing, evapotranspiration is negligible. Always dig a generous hole and loosen the soil at the bottom so roots can easily penetrate. Be careful not to plant any deeper than the tree or shrub was at the nursery (look for where the dark patch on the stem ends) as this will impede development. Firm the soil down around your new plants, but don’t trample too hard as you don’t want to crush all the air out of the soil.
But the perhaps greatest miracle...
If you visit your garden center in autumn, there will be plenty stock of each plant you’re looking for. You are likely to have the widest choice of varieties, sizes, and types and all the plants on offer have made their journey through the growing season – they are bigger, stronger and more viable than they were in spring. This makes them very good value for money and you may even, if you plant them now, get some visual benefit before next spring.