Partly by design and partly by accident, there were a good few bulbs which missed going into the ground back in the autumn and had been happily growing in plant pots over the past few months.

The accidental part is that the filthy wet weather kept me away from the borders for much of the autumn and winter (sic) when bulbs such as Narcissus and Allium should have been going in. Bulbs being, as they are, almost entirely self-sufficient they do not harm from being grown in pots for a time. This applies whether the pots in question are large, ornamental planters or plain black plastic jobs. When I mean by ‘self-sufficient’ is that a bulb is essentially a package containing an entire miniature plant including embryonic leaf, stem and flower parts surrounded by fleshy scales (providing food for the young plant) and a basal plate (which produces roots). If you’ve ever left an onion in the bottom of the fridge, or left a bag of spring bulbs in the shed, you’ll know that they carry on growing quite well without going anywhere near the soil.

Of course, the best method is to ensure that you get all the bulbs into the ground as soon as you can when they arrive in the autumn. However, this isn’t – as last autumn proved – always as easy as it sounds. And the warmer, much wetter winters we seem to be having to get used to are not good news for most spring-flowering bulbs, which are prone to rotting if they get too soggy. Even here, on free-draining chalk, some Tulips in particular struggle to overwinter happily: on clay or poorly-drained ground, they are very unlikely to make it.

Rather than leaving unplanted bulbs in their bag, where chances are they will rot – and, deprived of the fresh energy they derive from being in the ground, they will almost certainly fail to survive for next year – put them into pots of peat-free compost (add a bit of grit to aid drainage) and let them quietly do their thing. 

The ‘by design’ element is that bulbs over-wintered in pots are an absolute boon at this time of year. However hard you try, there are always one or two ‘bald spots’ in the borders, where bulbs have either failed to grow, or – more probably – you overlooked a patch when planting. Sometimes this can be the result of cutting-back herbaceous plants which were still standing when the bulbs were planted, and which were spreading over soil which has now been revealed. Whatever the cause, having some extra bulbs in pots means that you can drop them in to cover the bare patches, providing more-or-less instant cover and colour.

This morning we put in several pots of ivory-white Narcissus ‘Thalia’ to bulk-up one border which was looking a bit sparse, as well as many pots of Allium ‘Purple Sensation’ which will provide both height and colour in a few weeks’ time. Alliums are renowned for having rather ugly, floppy foliage so they are better planted where the lower part of the plant will be covered by other growth, allowing the colourful globe-shaped flower heads to emerge into the air above.