How to plant bulbs in containers

27 September 2021

By Margaret Alston, Bumblebee Conservation Trust volunteer

It’s that time of year again! The autumn equinox has passed, so it must be time to start planting bulbs again. Here’s my step-by-step guide, plus which flower varieties I’m trying this year to help feed bumblebees.

Amazing Alliums

I’ve always been rather a traditional bulb planter, but last autumn I was given three ‘new’ kinds of bulbs to add to my rather unimaginative selection of daffodils and crocus. I dutifully planted my ‘gifts’ of ‘Honey Lily’, ‘Drumstick’ and ‘Graceful Beauty’ Alliums in containers, as I was unsure where to plant them in the garden. I was rewarded with the most amazingly wonderful and long lasting bee-friendly plants in late spring earlier this year!

These beautiful plants which bloomed in May and June were a huge success! Bumblebees loved them and planting them in containers enabled me to move them around as required.

My plan for this autumn, then, was to plant these bulbs again and to join in the ‘Bee the Change’ idea of trying out more and new ways to help bumblebees and other bees by planting different things. I chose a selection of old favourites and added a few new ones including Allium moly and Allium azureum (also known as Allium caeruleum), which have gorgeous colour combinations and are supposedly bumblebee-friendly… We shall see!

How I plant my bulbs

So, now to the bulb planting, which to me is always a traditional and joyful occasion, coming at the end of summer and beginning of autumn when sadly, summer plants are passing over, but the anticipation of next year’s blooms is there within the new bulbs.

First of all, I set my bulbs out in order of height to which they will grow. I then gather up, dust down and set out all my available pots and containers which have often been lurking in various places around the garden.

Next comes the planting mixture. I mix half and half of ‘bulb planting’ and ‘multipurpose’ peat-free compost. Garden centres fortunately are now well stocked with all kinds of peat-free compost. I also add some horticultural grit and perlite for good drainage.

Now for the exciting bit – I’m ready to plant! Each pack of bulbs usually has information about depth and spacing of bulbs. I try to go with the depth, but would say that when planting in containers, bulbs can be set closer together than advised.

Starting with my ‘Honey Lily’ Alliums which do grow quite tall, I select my biggest pots. To help with drainage, in the bottom I sometimes put an upturned pot, some grit or some old crocks (broken bits of terracotta pot) and then I fill my pot to the required depth.

I space out my bulbs, add more mixture up to about an inch from the top, then put a layer of horticultural grit on top. This I think looks good, and protects the planted bulbs throughout the winter.

Treats for bumblebees

Next, I plant my Allium Azureum (a new variety for me), then my last year’s favourite ‘Drumstick Allium’ which grows very tall and slim just like a drumstick. The pots I used last year were rather shallow so I went for deeper pots this year. They take a while to bloom, going through many stages, but from the beginning of July until mid-September they attract bumblebees (especially males in late summer who linger drunkenly on the blooms through the night sometimes… so comical to watch!)

Next up is the ‘Graceful Beauty’ allium, which really lives up to her name, and then, some grape hyacinth varieties (trying some beautiful white ones too this year). Last but not least is ever reliable crocus. There are so many varieties of this cheerful little flower, always the first to appear in our garden in February and a welcome sight for the emerging queen bumblebees.

Now to find a place to put all these containers. I generally just group them round the garden, amongst borders, on paths, patios or wherever looks good – another good reason to plant in pots. As the bulbs start to come up, you can always regroup and alter their position. Planted bulbs also make a great gift!

And there you have it… my autumn bulb planting in containers!

Happy planting to everyone! Do share photos and ideas with the Bumblebee Conservation Trust, and why not try some different bulbs, become more bumblebee-friendly in your planting, and Bee the Change!