Choosing good seeds and potting soil is a must right now, even if according to the Covid rules “click and collect” is the only way to shop in a garden center.

Peat has traditionally been a key ingredient in most composts, but no responsible gardener would dream of using it right now.

Peat bogs are the second largest carbon store in the world after the oceans and contain ten times more CO2 per hectare than any other country, including forests.

After removing 90% of our own peat bogs, the horticultural industry is now importing 70% of the products currently in use.

There are many alternatives to peat and we owe it to the planet to use them. It is true that in the past, many compost makers have come up with inadequate recipes, like which one? Gardening has been tried and tested over the past 30 years. However, that is changing and reliable peat-free composts are now available.

The ace of peat had been good moisture retention. But there are now suitable competitors. Coconut, wood fibers, wood bark and wool prevent water from flowing past needy roots.

Coconut is a by-product of the coconut industry in Sri Lanka. During production, fibers are extracted from coconut shells and cleaned with steel combs to create fine material. Like peat, coconut retains moisture efficiently, but is difficult to rehydrate if left to dry out.

A good soil structure is crucial for moisture retention. As we all know, water flows right through folded compost in a pot. Processed wood chips help prevent this from happening.

The wood chips are wetted, pressurized and heated, making them a fluffier material. This often makes up around 50% of the finished compost. Manufacturers add nitrogen fertilizers to compensate for the “nitrogen robbery” caused by wood during degradation. Composted bark, a by-product of the conifer industry, also improves structure. It is ground and composted until the tannins are depleted.

A combination of wool and bracken is an exciting new material that allows the creation of small air pockets that are central to good structure.

Wool also contains the valuable nutrients, NPK nitrogen, phosphorus and potassium are the main elements that determine plant growth. Very roughly, phosphorus plays a key role in root development, nitrogen for stems and leaves, and potassium for fruit and flower formation.

Research carried out for the Welsh Government has shown that wool contains around 10% more nitrogen than comparable commercial products. Over a period of at least three months, nitrogen is slowly released from the wool so that no nitrogen replenishment is required. Although some phosphorus is present, a generous amount of potassium promotes good fruiting. This is released from lanolin in sheep wool oil, but don’t worry, its signature odor has been removed.

If, like me, you are now being sold with wool and bracken compost, you’ve come to the right place with Cumbrian company Dalefoot, whose wide range of composts are readily available.

I would also recommend the Sylvamix range including Sylvagrow made by Melcourt. Unfortunately, there are very few retail stores in Scotland for this wood-bark-based compost. However, you can find local suppliers on the Melcourt website.

New Horizon Compost generally scores well in the Which? Compost trials. It is primarily geared towards wood fiber and, unlike some peat-free brands, does not contain any green waste. This is composted garden waste that is collected in green bins. I am always sad that this valuable product needs to be treated with care.

Gardeners often put their “problem” waste in their green bins – woody stems and twigs and grass clippings. The grass is often contaminated with lawn pesticides. Since composting cannot remove all of the harmful chemicals, gardeners can poison their soil by using commercial green waste.

Plant of the week:

Crocus minimus ‘Spring Beauty’ has exquisite purple flowers. The outside of the petals is pinnate and veined a deep purple, making the flowers as attractively closed as when they open in the sun.