In the Maldon Museum in the Park there is a room dedicated to Maldon timber merchants and boatbuilders John Sadd. On the wall a painting commemorates a ship actually built in Bristol – HMS Rockrose. Nearby a large wooden heraldic plaque is inscribed with the words: 'Presented by the Lords Commissioners of the Admiralty to the Borough of Maldon to commemorate the adoption of HMS Rock Rose during warship week February 1942.'

Warship Weeks were National Savings campaigns introduced during World War II to sponsor warship construction. Communities bought into government bonds and National Savings Certificates, and were given targets according to size. A smaller community like Maldon would be expected to sponsor a destroyer or small escort ship.

Nationally, a total of £955,611,589 was raised, equivalent to £43.1 billion in 2019. The commitment didn't end there: charities, churches and schools would send letters, cards and gifts of gloves, socks and balaclavas to the crew. Plaques and photos would be exchanged.

HMS Rockrose (the name appears most often in this form, rather than Rock Rose) was a Flower-Class Corvette, arguably the most significant asset in the Battle of the Atlantic. Based on a steam whaler design, nearly 300 were built quickly and cheaply in small shipyards. They were designed to escort convoys and hunt U-Boats.

Naming ships after flowers seems odd, but this allowed a plentiful selection of names at a time when there were literally thousands of named Royal Navy ships. There's also a suggestion that the Navy took a mischievous pleasure in sinking the deadly U-Boats with such innocuously named ships. U-556, for example, was relentlessly hunted and sunk by HMS Gladiolus, assisted by HMS Nasturtium and HMS Celandine!

The vital role of these humble ships is made graphically clear in Nicholas Monsarrat's book, 'The Cruel Sea', and in Tom Hanks' recent film 'Greyhound'. Monsarrat, a serving officer in the War, described them as 'broad, chunky and graceless'. Their rounded hulls allowed them to weather heavy seas by bobbing and corkscrewing on the surface rather than digging into the waves like sleeker Royal Navy destroyers.

The crews paid a significant price for this – the motion was terrible, sleeping accommodation was cramped and primitive, and below decks was frequently wet. The rolling motion was extraordinary – it was said that they 'would roll on wet grass', and it could total 80 degrees – 40 degrees to either side. On the other hand, their seaworthiness meant that outside of combat, not a single sailor was lost overboard during the whole of the war.

HMS Rockrose was launched on 26 July 1941 and commissioned in November of that year. It was sold off to the South African Navy in October 1947, converted to merchant use in 1962 and finally broken up in 1967.

Although some 50 German and Italian submarines were sunk by Flower Class Corvettes, HMS Rockrose took on more typically humble duties: convoy escort and rescuing of survivors. In October 1942 she took on survivors (totalling 114) on four occasions, from the merchant ships 'Chickasaw City', 'Firethorn', 'Pantelis' and 'Ross'.

There may be readers who remember Maldon's wartime links with HMS Rockrose – I would love to hear their recollections.