Aubrieta is one of the lowest growing of all common hardy perennials, and gives us a wide range of flower colours for very little trouble or care on our part.
Why is it that many of the 'easy to care for' plants get neglected? Aubrieta is a plant that comes to mind. A little bit of attention goes a long way with this low growing evergreen perennial. An annual clip just after flowering, and instead of the long dangly straw-like shoots with flowers hanging limply on the ends, you will be repaid firstly with fresh foliage clothing the whole plant throughout the summer months, and a dense carpet of flowers the following spring.
I suppose that the main reason for not giving them a trim is the fact that they are normally 'covering' something up! Be brave. They will soon re-grow and do the camouflage job but with fresh grey-green foliage instead of bare stems.
If you are the owner of an untrimmed Aubrieta, have a look at where the flowers grow from next spring and you will see that it flowers from the foliage area and not from the bare prostrate stems.
Aubrieta should be trimmed right after flowering and not later in the year when an un-trimmed plant starts to look a little untidy. If you leave it until mid summer or later, you will be preventing it from flowering the next year!
As a rough guide, Aubrieta should be cut back to half its size or even more. Yes, as much as that!
There is very little else to say about how to care for Aubrieta. For the most part - and the rest of the year - they are quite happy to be ignored. In fact, after the trimming, less is more!
Aubrieta will grow anywhere that is dry and either sunny or part shade. Soil type is not an issue with them but avoid heavy clay soils which tend to become waterlogged in the winter. Stone walls, dry stony banks, containers, border edging, under roses as a carpet, the rock garden. Get the idea? Anywhere, and they do not have to trail down over a wall, though they look fully at home in that situation, and also help to cover up the fact that the wall might need maintenance!
In all, it is a good ground covering plant, and well suited to growing as a colourful carpet of flowers in early spring, and dense foliage cover throughout the summer.
Aubrieta are members of the cabbage family – Brassicaceae. If you grow cabbages, then you will know that they prefer lime soils. So it is with the Aubrieta, BUT they will do well in other soils. Their natural habitat is in limestone rock areas, though some also grow in woodland situations. The latter are not the ones that we normally use for garden planting.
Aubrieta can be grown from seed, which is a good method if you want a wider range of colours. Sow in late spring in a cool place, and pot grow for a few months before planting out in the flowering positions in the autumn.
If you have a prize specimen that you wish to increase, then they can be rooted from softwood cuttings in early summer or ripe cuttings in late summer.
By far the easiest and most productive method I have see, is by simply twisting a wad of stems off straight after flowering, and pushing it deep into soft soil! This has the effect of the all important pruning back as well. The advantage of this method, being that you will get larger plants more quickly than you would by the traditional ‘cuttings’ methods.
They may get attacked by greenfly, which is easy to wash off or spray against. The larger plants tend to be a good ‘home’ for snails in particular throughout the winter months. Slug damage in the spring is minimal.
I have never heard of a case of them suffering from the cabbage problem of clubroot, but possible!
Flea beetles sometimes, but really not a problem.
Keep them growing healthy by doing little more than the annual trim, and they should grow through any minor problems.