Blackberries or Rubus agg.

An abundant crop of blackberries on my allotment

With my recent research into the Bagnall Herbarium at Birmingham Museum I’ve been looking through many boxes of this large and diverse group of ‘blackberries’.

Bagnall seem to be fascinated by them and I discovered also there is a lot more to them than you first may think!

Pictures by Matt Summers.

The time of writing coincides also with the blackberry season, I’ve been picking them now for weeks on one of my allotments, ready for all those winter puddings!

There is a lovely poem by Walt Whitman about blackberry in ‘Song of Myself’ (1855) mentioned in ‘Hedgerow Medicine’ .

 It is a very long poem (over 1300 lines) if you care to read it all here

I believe a leaf of grass is no less than the journey work of the stars/ …. and the running blackberry would adorn the parlors of heaven.

But another writer just refer to blackberry as a ‘primitive thug’ (in J. Roberts’s history of fruit and vegetables (2001).

For me it is mainly positive because of its lovely fruit I gladly pick each year and eat in my breakfast cereal or as a preserve mixed with apple in my ‘famous’ Dutch appletart mixes.

I also find it a very attractive plant mixed into a wild hedgerow: a picture of just one example together with Honeysuckle on the Dorset coast

Blackberry flower with Honeysuckle!

General information:

Blackberries are perennial plants which typically bear biennial stems (“canes”) from this perennial root system. It is part of the large woody genera of the Rosaceae family, of which I did another post, published 5th June 2020.

It usually is a vigorous, sprawling and climbing plant which does this with means of its sharp, curved prickles that are often erroneously called thorns. These prickles can tear through denim with ease and make the plant very difficult to navigate around.

But prickle-free cultivars have been developed, such as cultivar Merton Thornless, if you want to plant them in your own garden.  

It grows in nearly every known habitat and especially or too well in fertile soil. Each individual blackberry, ripens from June until November and when ripe, is made up of 20-50 single seeds known as drupelets that are small, juice-filled and are a deep purplish black.

 Technically, they are an ‘aggregate fruit’ (another meaning of that word later) rather than a berry.

Classification of the Blackberry:

The Blackberry is in the  genus Rubus which is part of the Rose family and  number 48 in the New Flora of the British Isles, 4th Edition by Stace.

The Rubus has several native species, including R. idaeus or Raspberry but the one we probably know best is called the Blackberry, the useful, edible one or the Bramble when it is the nasty, spiny one!

The Scientific name of the Blackberry or Bramble used to be Rubus fruticosus but it is now often just called Rubus aggr. This is what Stace has to say about it:

R. fruticosus is an aggregate species made up of several hundred slightly differing microspecies. The reason for this is that most seed is produced by a non-sexual method (called apomixis) and is therefore genetically identical to the parent plant. On occasions when sexual production of seed takes place the offspring will all be slightly different from the parent plant and will then usually reproduce as a new species by means of apomixy.

Modern treatment of this aggregate divides the genus Rubus in not only species but also as said before over 400 microspecies, subgenera, subsections and finally series.

For a a fabulous account of this classification I like to refer to a website by John Norton Ecologist called ‘Brambles of the British Isles‘.

Ethnobotanical uses:

As Food:

  • Blackberries are delicious raw or can be preserved and made into jelly or jam.

Blackberries contain a wide array of important nutrients including potassium, magnesium and calcium, as well as vitamins A, C, E and most of our B vitamins. They are also a rich source of anthocyanins, powerful antioxidants that give blackberries their deep purple colour.

There are plenty of recipes on line and I may try some jam this year with the surplus fruit. Here is one recipe I found.

From a useful website/blog I discovered the following:

  • Perhaps less well known is the fact that the young leaves and shoots in spring and early summer are also edible.

Collect them whilst the thorns are still completely soft to the touch and with the shoots they shoot snap off crisply.  Both leaves and shoots can be boiled or steamed and served as a vegetable, and they can be added to soups like nettle soup.  The leaves are nice blanched for a few minutes in boiling water, drained and then fried in olive oil with onions and garlic.  

The young leaves can also be eaten raw when very young and have an unusual coconut like flavour and the young stems can be peeled and eaten in salads.  

  • The leaves can also be made into a tea, by partially fermenting the leaves you can actually make a tea which is on a par with genuine black tea.

Medicinal Uses:

  • The root-bark and the leaves are strongly astringent, depurative, diuretic, tonic and vulnerary.
  • They make an excellent remedy for dysentery, diarrhoea, haemorrhoids, cystitis etc, the root is the most astringent part to use.
  • Externally, they are used as a gargle to treat sore throats, mouth ulcers and gum inflammations.
  • A decoction of the leaves is useful as a gargle in treating thrush and also makes a good general mouthwash.

Other Uses:

  • A purple to dull blue dye is obtained from the fruit
  • A fibre is obtained from the stem and used to make twine
  • The flowers and fruits are very beneficial to a host of wildlife. Plants are spread by seed deposited in the droppings of birds and mammals. They often spring up in burnt-over, logged or abandoned land and
  • Make an excellent pioneer species, creating the right conditions for woodland trees to move in. The trees will often grow in the middle of a clump of blackberries, the prickly stems protecting them from rabbits!
  • Plants form dense thickets and this makes excellent cover for birds.
  • They regenerate freely after being cut back
  • Blackberries are useful to train as a hedge, along horizontal wires and against the wall. It has biennial stems, produces a number of new stems each year from the perennial rootstock, these stems fruit in their second year and then die.
  • There are many good cultivars in circulation producing large fruit or thorn less varieties as well.
  • Very easily grown. It tolerates poor soils and established plants are drought resistant. Succeeds in sun or semi-shade, though it fruits less well in the shade or against a north facing wall, the fruit will ripen later. Plants tolerate quite severe exposure too and can be useful for wind protection of more tender plants.
  • My own found use is for an attractive and vandal proof Christmas wreath! Their long, new stems can be easily manipulated and bend into a ring, without the use of wire or string. Then other attractive material can be pushed into those prickly stems. I have used the golden coloured, dry fronds of bracken, the little cones on stems of the larch, birch twigs, conifer and other materials in the past.    

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