Lilac Karl Ludwig Outfit with Multicoloured Accents

This colourful outfit, perfect for the warmer months, is comprised of a v-neck, collarless, double-breasted coat in lilac crepe, a silk dress in a slightly warmer shade of lilac, with a multi-coloured floral print, both by Karl Ludwig, and a lilac straw Angela Kelly hat trimmed with a large twirl of multi-coloured straw ribbons and feathers on one side.

This look was debuted on 19 June 2009, Day 4 of Royal Ascot. The Queen accessorized it with the large diamond City of London Lily brooch and cream leather handbag and shoes:

 

Almost exactly a year later, on 11 June 2010, the Queen repeated it to attend Trooping the Colour. The Household Cavalary badge, as usual, was worn to the event:

On 3 July 2014, after a spell out of the public eye, the outfit reappeared, worn to a commemorative service for the Scottish National War Memorial at Edinburgh Castle, during Holyrood Week (Daily Mail article here). This time the Queen paired it with the diamond six-petal flower brooch:

On 5 July 2015, the Queen wore it again to attend church at St Mary Magadalene on the Sandringham estate a few hours before the christening of her great-granddaughter Princess Charlotte of Cambridge (Daily Mail article here). Aptly, the Cambridge Pearl Pendant brooch was worn:

Flowery Angela Kelly Ensamble

This double-breasted lavender coat, floral silk dress and straw hat with dark purple bow and flower trim to one side, all by Angela Kelly was first worn on 20 June 2013, Ladies' Day at Royal Ascot, a particularly happy day for the Queen as her horse, Estimate, won the Gold Cup, a first for a reigning monarch. The Kent Amethyst brooch nicely complemented the lavender hue of the coat:

 

With her jockey Ryan Moore:

This lovely ensamble was repeated about a year later, on 21 May 2014, for a Buckingham Palace garden party, this time accessorised with the Carrington Sapphire Feather brooch:

It's impossible to be sure, due to the low resolution of the images available, but I'm convinced this silk dress the Queen wore on 23 July 2014 to receive the Governor General of Grenada, Dame Cecile La Grenade, at Buckingham Palace is the one from this look - the colour and pattern seem to match, although higher resolution pics are definitely called for!