Violas are typically lower growing than pansies, with smaller, more abundant flowers. Many violas form a trailing habit and look fabulous in a hanging basket, patio pot or window box. Don’t be put off by their smaller size – in fact violas will produce more flowers per plant than a pansy! Here’s our step by step guide to fabulous violas.
Violas are profuse, low-growing cottage garden perennials. The colour combinations you can achieve are myriad – purples, lilacs, pinks, blues and magentas. Varieties available cover trailing violas, double-flowered and colour-changing flowers, as well as violas with particularly striking, variegated foliage. Viola flowers are also edible – you can add a dash of colour to a salad or as a garnish, or use them in jams, cakes or as decoration on the top of biscuits!

Source: https://www.gardeningdirect.co.uk/violas-guide

Primroses provide you with early spring blooms in almost every color of the rainbow. They prefer cool temperatures, a rich humus soil (lots of compost and leaf mold) and partial shade. They appreciate full sun in the spring, but must have semi-shade as the temperatures warm. They are quite tolerant of being transplanted, even when they are in bloom. They should be planted in a cool, partly shady area in the garden with rich, well-draining, slightly acid soil (pH 6.5). Primroses need to be planted so that their crown is right at soil level and at least six inches apart.

Source: http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=b564

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