I'm about to buy and plant out some buddleia bushes (link if you're curious about type)
Are there any sensible options for either interplanting with buddleia, or planting in front/around the buddleia, that will botanically and aesthetically complement each other.
I'm imagining something that might flower (or otherwise be colourful) at times when the buddleia is dying/being cut back, and that won't detrimentally compete for nutrients.
The link you provided seems to say there are 3 separate plants - Buddleia tricolor is available as one plant with 3 different coloured blooms on it, so I'm not certain whether you will receive 3 plants in one pot which effectively act as a single plant because they may be impossible to separate at the roots anyway. Either way, this is a Buddleia davidii variety - that means it needs cutting down to within 2 inches of the old wood every March to keep a tidier growth habit, after the first year or so. Average height between ten and twelve feet, with a spread of up to ten feet at the top of the plant - the stems have an arching growth habit. Even though you cut it right down to virtually a stump in spring, it will put on up to ten feet of growth in a season once mature.
You can certainly plant round it, but only if you are planting into a sizeable bed, when it should be placed towards the back, but with enough room for its branches to spread out without being crushed against a fence or wall. Something evergreen is a good idea because buddleia is deciduous, and after the first 3 or 4 years, there will be a noticeable 'stump' of bare wood towards the base which an evergreen shrub will block from view, so maybe a Choisya variety if there's room - these flower around May, well before the Buddleia will. Choisya Sundance has yellow leaves; Choisya ternata 'Aztec Pearl' has green leaves, but there are a couple of other varieties - all have white scented flowers and all reach about 6 feet with a similar spread. Other options include Convulvulus cneorum, a lower growing,rounded grey leaved evergreen shrub with tubular white flowers in May, and the deciduous Spirea varieties - these usually have pink flowers in May/June and there are several yellow leaved varieties; 'Goldflame' is a good one with a height and spread of 4-5 feet, Magic Carpet is similar but lower growing. Cistus corbariensis is a hardy, evergreen plant with white flowers in May that does not get as large as Choisya varieties, making around four feet in height with a spread of up to five feet. There are other varieties of Cistus available such as Cistus purpurea with pink flowers- this is not quite as hardy, but in London, it should be fine. All plants mentioned, including the Buddleia, prefer full sun if possible.
Why not perennializing some daffodil, or other spring flowering bulb around its feet, to at least give you some action when it’s bare or cut back? A white variety might be handsome.
Good luck!
I am afraid there is no sensible option that satisfies your requirements. Your idea is as if belonging to some science fiction.
There is one option that is perhaps slightly on the line of your ideas. Instead of pruning buddleja in spring this way:
... you can prune it this way:
(in case of Tricolor, you will of course have three plants coming from the ground, I didn't draw this for simplicity)
By doing this, you will achieve more natural look for couple of months every year until buddleia grows large enough.
You could consider the evergreen Pheasant Grass (Anemanthele lessoniana) which provides year-round colour and movement and a contrasting leaf style, plus it hides the stump in winter, together with a pale blue geranium (perhaps Roxanne or Phillipe Valpelle) for long-lasting contrasting summer colour. I also include Tulips in my planting scheme in front of the grass, for earlier flower colour. Spring bulbs before the tulips as suggested at https://gardening.stackexchange.com/a/59411/36191 would work well (where I live, I'd go for snowdrops and bluebells).
