© Denzil Green
The bramble bushes that they grow on flower in clusters, which then develop into berries somewhat resembling raspberries in that a “single” berry is multi-clustered. In urban settings, we have to pay dearly for these, but in rural settings, they are easily gathered along roads. Just mind the thorns.
When ripe, the berries will be black, glossy, and soft without being mooshy. If you are making preserves, you may want slightly less ripe ones which will be a bit harder and have a bit more pectin, though they will also be tart. Blackberries develop mould very quickly when crushed, so if you are buying them fresh in a container check the container for any signs of juice will which indicate crushed berries.
A Blackberry isn’t a “true” berry. It is an agglomeration of individual berries known as a “drupelet.”
When harvested in August, they may still be slightly tart. Into September, and they’ll have reached their full sweetness. Both stages of ripeness are acceptable. Traditionally, they should not be picked after Michaelmas (29 September.) See calendar entry on “Devil Spits Day.”
Wash only when you are ready to use (or freeze) them. If you purée them, you may wish to strain them to remove the seeds.
The pH of blackberries ranges from 3.85 to 4.5 FDA. Approximate pH of Foods and Food Products. April 2007. Accessed August 2017 at http://www.vldhealth.org/pdf/environmentalPDF/foodPH2007.pdf Consequently, if you are home canning them, consider adding a small amount of bottled lemon juice or citric acid to ensure a pH well below the upper safe cut off of 4.6.
Blackberries contain twice as much Vitamin C as blueberries.
A generous handful of Blackberries contains 8 g of fibre (1/3 of the UK recommended daily amount), and half of your recommended daily intake of manganese.
They also contain folic acid (aka Vitamin B9, aka folate.)
1 pound blackberries = 450 g = 3 1/2 cups blackberries = 1 1/2 pints = 1 1/2 cup mashed
1 pint punnet, whole blackberries = 2 cups = 300 g
1 dry pint blackberries = approximately 350 g (12 oz)
500 g / 1 lb blackberries = approximately 2 2/3 cups whole = approximately 400 ml (1 2/3 cups), crushed 
Pick over and discard any crushed or mouldy berries. Refrigerate unwashed for up to two days spread out and covered with dampened paper towel.
Blackberries freeze well and stay whole after thawing — that is to say, they don’t collapse into moosh.
Blackberries grow wild in many English hedge-rows. The alternative name, Brambleberries (or Bramberries), comes from an old name for the bush “brambel”, meaning prickly.
They were known and used by the Hebrews and the Greeks.
 Ball / Bernardin Complete Guide, 2015, page 427.
Peters, Rick. Seasonal food: blackberries. Manchester: The Guardian. 9 September 2010.
Venning, Annabel. Pick of the superfruits: There’s more fibre in a handful of blackberries than in two shredded wheat. London: Daily Mail. 20 August 2011.
|↑1||FDA. Approximate pH of Foods and Food Products. April 2007. Accessed August 2017 at http://www.vldhealth.org/pdf/environmentalPDF/foodPH2007.pdf|