#27 Comfrey Power

If you are a Permie or someone who has practised holistic gardening then it’s likely in this episode I’ll be preaching to the converted. That’s because comfrey is a gardener's magic pixie dust that has been used for aeons. I can’t believe I totally left this amazing herb out of the last episode when we were talking about fertilisers. That’s what middle aged female brain fog looks like. Anyhoo that's a different podcast… Now let’s chat about comfrey.

So what is it?

Comfrey is a herbaceous shrub that's native to Europe and Asia but now grows in most parts of the world. It produces large dark green leaves that are hairy and soft. The stems have soft spikes that are similar to borage. In fact comfrey and borage care cousins.

It produces little purple, pink and or white flowers during late spring into summer.

There are 2 types of comfrey referred to as Russian or Bocking 14 comfrey and True or common comfrey.

True or common comfrey produces white flowers and produces seeds which means it can be spread. In some areas this is a benefit but in other areas it can become an invasive weed.

Russian or Bocking 14 comfrey is sterile and won’t self seed. It’s easily propagated so this is the variety I grow and recommend to anyone. More about propagation soon.

Comfrey is super resilient in most gardens. It prefers protection from hot afternoon summer sun and prefers free draining soil but will grow in just about anywhere. Ours is thriving in super heavy clay soil that has been waterlogged for the last 6 months and it’s as happy as a pig in mud.

I threw about 10 starters in the ground in 2019 before the heat wave that saw the east coast of Australia was on fire, temperatures reached over 40deg c + (104f) many days and the whole place was like a tinderbox. Everything on our property was brown and crunchy. We didn’t water anything in an effort to save what little precious water we had. I think I threw a few buckets of water from the shower on them. That was it. We had a 50% success rate and that was 50% more than I was expecting.
So you can see that they can take a beating and still find a way to thrive.

Why is it a must in every garden ?

Comfrey has super roots. They can penetrate down to 2 metres or more in ideal conditions.
The roots essentially mine macro and micro nutrients that other plants can’t get to. They then store these delicious nutrients throughout the plant with a good portion being stored in the shrubby leaf mass. It’s often referred to as a dynamic accumulator for this reason.

This means when we use comfrey in the garden the nutrients are returned to the soil but are now available to the shallow rooted plants.

The super roots can also help to break up compacted earth and their leaves add organic matter back into the soil.

The flowers provide nectar and pollen for many species. The thick growth provides habitat for small insects and it attracts some of my favourite pest management buddies. Lacewings lay eggs on comfrey leaves and parasitoid wasps and spiders are often seen around or on comfrey.

Another benefit is the dense nature of the plant. Because it grows so thick and clumps together it often crowds out anything else in it’s way which is awesome if you have a weed or grass invasion of the unwanted kind. Be aware of how comfrey may impact on its neighbours before planting.

Before we get into the usage side of things we need to know how to propagate our comfrey.

Listen very closely as it’s a bit complex… You dig up a whole or partial plant, you take cuttings from the root about 5cm long and lay them horizontally in a prepared garden site or in a pot. Keep it moist until several leaves appear.

So you see… super complicated.

Now we have comfrey growing. What and how do you use it?

There are lots of ways to use this superwoman of a plant.

Put it in your compost as an activator. The nutrients will break down and give your compost, hot or cold, a kicker.

Chop and drop. It can be totally cut it back up to 3 times a year in fact you can mow the stuff and it will come back. Or you can chop as much as needed. Drop the leaves on the garden to break down, adding organic matter and releasing those nutrients into the top soil.

Use it as a living mulch around trees or garden edges.

Placed at the bottom of planting holes either in pots or in the garden. The leaves will break down and feed the plants as they establish.

Chickens love it. Add a little bit to their breakfast. You will see yellow yolks like sunflowers. It can be used as a treat feed for other animals too but using it sparingly and do research before feeding.

Make tea. Not for you but for your garden. Fill a bucket, bin or bath with as much comfrey as you can fit. Ideally chop up the leaves to speed up the process and cover it with water and cover it with a lid. And for the love of all things…. Cover it very well. I will warn you. This stuff stinks. The more it ferments the stinker it gets.

Like any good tea it needs to steep. Let sit for at least a week but if you want a nice strong tea aim for 3-6 weeks.

If you leave it for a full 6 weeks it will be a sludge. That's a good thing. It means all those nutrients are now in your tea. Strain the tea using a cloth or fine strainer.

It needs to be diluted but the ratio will depend on how concentrated your tea is. There is no absolute rule so you can’t go too far wrong.
If you left it 6 weeks then aim for a 1:9-10 ratio, if you left for a week then a 1:2 would be fine. 3 weeks would be about 1:4 ratio. Adjust accordingly.

These are guides only. If you leave it for several months it will still be usable.

You can use it as a foliar spray using a pump spray bottle or add it directly to soil via a watering can. If you have a hose end sprayer bottle you can use that but you need to make sure your tea is super strong and has been strained through a very fine cloth to prevent any blockages. Adjust the flow to suit your tea.

I am planning on pimping my compost tea process so I can have continuous batches brewing. I am going to use 2 60litre outdoor garbage bins. The bottom bin will have a tap and the top bin that will stack inside the other will have holes along the bottom, a layer of small gauge wire and a few layers of heavy duty fly screen. This way I can harvest the tea without having to open the bins. Once it’s done I will clean it out and start over. The goal will be to have 3 of these at various stages so I can have ready tea every 2 weeks if I need it. I will have to up my comfrey game, to make sure I have enough to harvest on a consistent basis.


It can also be made into a salve or infused oil for healing. I haven’t used it like this so I can’t personally attest to its benefits but there is a lot of interesting information out there about the medicinal properties of comfrey. In the past it has been consumed as a vegetable and herbal tea however we now know that it is somewhat toxic to humans and in larger doses to livestock.

It has potential carcinogenic properties. So don’t go eating it and if you are going to explore herbal medicines be sure to do a butt load of research as there are whispers that these toxic effects can also be through dermal absorption of high concentrated doses. Again do your own thorough research.


Once you're done throw any spent leaves and sludge into your compost or bury them in your garden.

So now you can see why comfrey is the superwoman of the garden world. I knew the benefits of comfrey for a long time but I didn’t really know for myself until I started using it.