The compost used for plants can provide the right growing conditions for healthy plants. Making careful selection of a suitable potting mix is vital. Knowing what is likely to be in a mix and why it is there helps to make a more informed decision.
Keeping house or garden plants looking strong and healthy depends on many factors. There are plants that require lots of sunlight, while others prefer to be kept in the shade. Some plants require more water and a higher humidity than others. Some acid loving plants such as camellia or rhododendron will require an ericaceous compost with a lower pH. Choosing the right type of soil is essential to get the most out of your plants.
One mistake many plant owners make is using garden soil for their pot plants. While this may seem like a cheap alternative to buying a bag of potting mix, it may actually do more harm than good. Garden soil may be full of weeds, pests or disease that can do serious damage to a potted plant. Also garden soil may lack the vital nutrients that your potted plants need.
Mulit-purpose is a middling mix between seed compost and potting compost and can be used as a substitute for either. It is the best choice if you’re planting small patio pots, hanging baskets, herbs and flowering bedding plants. But it has less nutrients than potting compost, so add fertilisers if you’re planting larger varieties. It is not suitable for established trees and shrubs.
Seed compost is a mixture designed for sowing seeds into. It’s finer and less lumpy than standard potting compost and is also light and well-drained. You can also use seed compost to repot seedlings and young plants. But it doesn’t have enough nutrients to support larger plants.
Peat moss consists of partially decomposed, ground up bog plant material. Perfect for African violets, begonias, ferns and other plants with a preference for moist environments. Peat moss improves the retention of water and keeps the compost light.
Bark helps to retain soil moisture, suppress weed growth and will gradually improve the structure of your soil. The large chunks of composted bark stop the tight compacting of potting, thereby assisting drainage and keeping air circulation optimal. This type of material is typically added to mixes for bromeliads, orchids and similar plants.
Perlite are the little white puffs found in potting mixes designed for house plants. Thanks to thousands of minuscule air pockets, perlite is able to rapidly soak up and then release water. It is perfect for drainage and overall water regulation. Potting mixes for succulents have a particularly high quantity of perlite added to them for this very reason.
Vermiculite, produced from natural deposits of minerals, looks similar to tiny flakes of gold. It is added to many potting mixes to assist aeration and absorb water and minerals, which are then slowly released into the soil. This material can soak up and eventually release multiples of its own weight in minerals and water.
Which type of potting mix to use ultimately depends on the requirements of any given plant to be potted. Taking a little time to learn about these requirements and taking note of the ingredients on a bag of compost before purchasing it will help to ensure a happy, healthy life for house plants for years to come.