Why Autumn is the Best Time for Planting

A lot of people tend to think that large-scale planting is best done in the spring. This isn’t actually the case though for a number of different reasons.

To have a happy and healthy plant that will thrive in the long-term, you need to make sure that it has a good strong root system. Therefore, establishing this needs to be of primary importance ahead of the appearance of the plant above ground. In order to have a good strong root system you need to try to provide the best possible conditions with the minimum amount of stress for the plant. This is why autumn is the best time for planting. As we head out of summer and into autumn, you find that the soil will be nice and warm still. This means that root development will be quicker than in springtime planting, where we are heading out of winter with the soil temperatures obviously being much colder.

Another factor to consider is the stress on the plant with regards to temperatures and day length. With autumn planting the stress on the plants becomes less and less with each day that passes. The average temperatures start to drop, and the days become shorter and shorter meaning that the plants can take their focus off the top growth and focus on that all-important root development. Again, if that is compared with springtime planting then we have the opposite happening. The average temperatures are increasing, the days are getting longer and longer, and the plant is wanting to actively grow.

The root system of a Persicaria bistorta 'Superba' ready to be planted out

Knock-on effects of these factors means that there is far less watering that is required with autumn planting. This is good from both a sustainability point of view, and a money-saving one. Plants always need to be watered in well immediately after planting, and depending on the weather at the time, watering may need to continue until mid-October. However, it is rarely needed beyond that as we usually have increased rainfall, as well as the plants tending to not use as much energy, with many herbaceous and deciduous plants going dormant over the winter months. The big advantage though comes the following spring. With autumn-planted plants having a more established root system there is less of a reliance on excessive watering. For springtime planting however, watering throughout the spring and summer months are essential in order to get that root development to a level where it can support the plant on top. Usually at this time of year the plants will be using huge amounts of energy in putting on new foliage growth, as well as flowering, and then often producing seed too.

My own garden being planted up in October 2019

In summary, autumn planting effectively gives all of your plants a 6 month head start. Whilst the one downside is that your borders may not have as much of an instant wow factor, the upsides are that you will have healthier and happier plants in the short-term, resulting in healthier and happier plants in the longer-term not requiring as much watering and attention. You may also be able to save money too, as many plants can be available cheaper in a different form. For example, bulbs can be bought as dry bulbs instead of potted, as well as hedging and some other perennials being bought bare root as opposed to potted. On large-scale plantings these savings can be significant. Everybody’s gardens and situations can be different though, but with my knowledge and experience working in horticulture, I am able to help and advise with what is the best course of action to get the most out of your garden and plants.

Thanks for reading,

Jacob

My garden in April 2020 with most of the plants now having good established root systems ready to grow away on their own