Understanding what a microclimate is
A microclimate can be defined as all climatic conditions in a restricted space and, therefore, isolated from the environment in its entirety. So, in your garden, if you pay attention, you can notice variations depending on the different places, whether in terms of temperature, hygrometry, influence of wind, sunshine, precocity or delay melting snow or frost, etc.
These differences can be significant, even in a small space, and they play an important role in the development and durability of your plants. It is therefore necessary to analyze these conditions in order to identify these different microclimates and to know which plant to plant and where according to its needs. To do this, different means are at your disposal. We describe them to you below.
Look for visible natural clues
This search for clues is simply based on observing your garden.
Snow and frost
When it has snowed or frozen, it is interesting and very instructive to observe which areas are melting most quickly. Thanks to this observation you will be able to determine:
- areas where frost and snow persist longer, that is to say those which correspond to the coldest areas of your land and where it is wise to plant more hardy plants; And
- conversely, spaces where melting occurs firstthat is to say those which correspond to the zones which warm up the fastest and where it is wise to plant the coldest plants, as well as the first annuals in spring.
The relief of the garden
Another criterion to take into account when identifying the microclimates of your garden is the relief and mainly the difference between the raised areas and the low parts of your land:
- If your land is sloping or if you have a mound on this one, you will be able to take advantage of this configuration by installing plants which need perfectly drained soil and which fear excess water, because it causes their roots to rot. Indeed, as soon as there is a slope, drainage of water is ensured naturally since this slope allows its rapid flow.
- Conversely, in the lower parts, as the water will tend to stagnate, it is therefore preferable to focus on plants that like heavy and humid soil. But be careful, these areas, even if they are less exposed to the winds, are generally cooler.
Dead leaves
In autumn, when the dead leaves fall to the ground, it is the time to observe their movement to determine the prevailing winds. Here is what you can see and the conclusions you can draw:
- The places where dead leaves are swept away are areas subject to wind and, therefore, colder, because the wind tends to lower the temperature by several degrees. You must therefore avoid installing plants that are sensitive to frost or wind in these areas.
- On the other hand, the areas where dead leaves accumulate are either areas sheltered from the wind, or areas which are not on a passage corridor thereof. Being, for one reason or another, protected from the onslaught of the wind, they will be able to accommodate your most fragile plants.
The presence of water
If you notice areas in your garden where water is stagnating and creating puddles, this gives you two useful clues about the soil in these areas:
- The ground may have a clay trend which hinders the proper infiltration of water. If certain plants adapt perfectly to it, they should be chosen carefully.
- The soil is less well drained, which means that when planting, it may be necessary to add something to the soil in your garden to ensure drainage, such as sand or gravel.
The influence of trees
Trees also help create microclimates on land. In general, temperatures are cooler under the trees. However, it is important to differentiate between 2 types of trees:
- Deciduous trees : as they lose their leaves in winter, they allow the plants planted underneath to benefit from the sun in winter and their shade in summer. This type of exposure may be suitable for certain plants that appreciate being in the shade when the sun is scorching, such as camellias, hydrangeas, spring bulbs, etc.
- Evergreen trees : they retain their foliage all year round and thus provide cover, but also continuous shade. This is the ideal location for shade and humidity plants, such as ferns, hellebores, hostas, etc.
The influence of walls and hedges
On the one hand, buildings, whatever their size, and hedges block the winds and protect the plants located at their base from them, and, on the other hand, they create microclimates on a plot of land:
- Hedges filter the sun and regulate the humidity of the air. As a result, temperature differences are less significant near them. Near your hedges, you can plant plants that fear the scorching sun, as well as those that are sensitive to wind and frost.
- The walls play the same role, but we must also add the parameter of its exposure. At the foot of a south-facing wall, you must not forget that what will predominate will be heat, sunshine, but also drought and you must take this into account when buying plants. Conversely, a north-facing wall is almost always in the shade and creates a cool area. You can plant the same plants there that you would plant under an evergreen tree.
Search for clues with technical solutions
More technical means are also at your disposal to determine the microclimates of your garden.
The thermometer
A first solution to determining the microclimates in your garden is to take temperature readings at different points in your garden and at different times of the day. You can write down the different temperatures in a notebook to make a journal, but you can be sure that the temperature differences from one point to another will surprise you and will be very informative as to what you can plant in this or that corner of your garden.
The rain gauge
You can carry out the same experiment with rain gauges installed in different places in your garden. You will then see concretely that certain areas, such as those under evergreen trees, receive less rain than perfectly exposed areas. This is also information to take into consideration when planting your plants.
Compass
If you don’t have a compass, check on your cell phone, as they often have one. The advantage of a compass is that it is of great help in determining the different exposures of a terrain. Each exhibition offers criteria to consider for plants:
- West : plants installed in the west will benefit from the morning sun and be protected from the fiery rays of the afternoon.
- East : plants installed in the east will benefit from conditions which will be the exact opposite of those described above.
- South : plants will benefit from good sunlight throughout the day and higher temperatures.
- North : the plants will benefit from more shade and freshness.