The latest Aberglasney gardening column from the Carmarthen Journal

The latest Aberglasney gardening column (by head gardener Joseph Atkin) from the Carmarthen Journal newspaper - 
Mulching Why, When and What . . .
One of the most impressive winter sights is a well tended border being weed free nicely cultivated and maybe mulched.

What we do in our borders in the winter often decides how well the summer goes.

Much of the work in a border is actually best done in the winter leaving only staking weeding and dead heading for the summer or maybe watering in other parts of the country.
Mulching can be a really important part of the garden calendar and can be hugely beneficial or in some case can cause some serious problems.

But first of all what is mulch?

Well this is always up for discussion.

In my view, it is something you put on top of the soil to suppress weeds and or improve the soil. Gravels and aggregates can be used as weed suppressants but more commonly organic matter (composts) is used.
So what do they do?

Well they all suppress weeds keep the soil cooler in summer and warmer in winter and that’s it for the gravels and aggregates.

However, organic matter is very different as it improves soils.

It improves drainage, and the soils structure, one of the most confusing terms you here in gardening is moisture retentive but free draining as a recommendation.

Well it’s the soil structure that is being referred to here.

Generally, we want our soil to be like a sponge holding water and air, organic matter is one of the best materials for doing this.
Organic matter also increases the activity of microbes in the soil, helps it drain and reduces compaction.

So, altogether, it does a lot of good to the soil, with the help of worms mixing it into the soil.

At Aberglasney, it also helps protect the more tender plants from frost damage and helps drain the heavy clay.
So what is the best organic matter to use?

Well the two most important things are that it is well rotted and weed free no matter what it is.

Homemade compost is as good as anything but it often has weed seed in it.

Well rotted wood chip or shreddings is also a good weed suppressant but rots down more slowly. Peat is often used but is extremely expensive very bad for the environment and easily substituted.

Compost waste from the local tip has been very effective this year at Aberglasney there are many other good materials available.
It is important to know what plants want mulching and which don’t. Peony don’t like being mulched over but do appreciate it in the surrounding soil.

The way around this is to put a bucket around the crown of the plant while you mulch and remove it afterwards.

One of the big things to remember is most mulches are alkaline and can raise the pH of the soil so it’s always worth getting it checked before putting it on ericaceous (acid lovers) plants. Bracken mulch is usually the best for this job as it is specially made to be ericaceous composts bought from garden centres are usually quite safe as the bags should state the pH on them.
At Aberglasney, we mulch to a depth of 50mm for everything ad aim to do it biennially where appropriate. Places with sandy soils where drought is a problem often put a deeper covering.

It is important not to bury plants or bank it up against the stems of shrubs or trees.

Mulching can be done anytime but it is often best done in autumn or early winter so you get the benefit of frost protection and it’s easier to apply when the plants are cut back. Mulches have numerous advantages and can really make life easier and give a better display.
Tips for the Week
· Mulching?
· Put out bird feeders as they are really good garden predators
· Check plants are properly protected ready for this cold spell
· Plan your vegetable garden and seed sowing if you have not already done so
· Christmas is a great time to look through the catalogues and choose annuals for next year
· Planning garden visits and shows you would like to visit is also a good thing to do over Christmas 

Wood chip makes an excellent mulch but needs to be well rotted.

 Home made Aberglasney compost is an excellent soil improver but may contain weeds.

Composted greenwaste makes an excellent soil improver. 

Chipped bark provides excellent protection against frost.