This is the time of year when we hunt far and wide for those prized berries for our Christmas wreaths, ideally finding a holly with plenty of berries and not too many prickles.
Most hollies are dioecious, which means the plant is either male OR female. You will need one of each for the female plant to bear berries. There are, of course, exceptions to the rule. Ilex aquifolium ‘J.C. van Tol’ and I. aquifolium ‘Pyramidalis’ are widely sold as self-fertile cultivars and need no partners. But mainly there are males or females, and this is should be indicated on the garden centre label.
Never go by just their names. While girly names like ‘Madame Briot’ and ‘Golden Milkmaid’ are often female, the ‘Golden King’ is female and the ‘Silver Queen’ is a male! So avoid having a bunch of queens, and no berries, by double-checking the names and sexes before purchasing.
Buying the right holly is quite straightforward, but identifying whether you have a male or female in your garden when none are producing berries becomes tricky. You could have a bunch of blokes with no hope of producing a berry or you could have a group of lovely ladies just waiting for their ‘Blue Prince’ (a male) to come along.
A slight difference in the flowers can be spotted, if you fancy having the challenge of examining the blooms in spring. All the flowers have all the parts; but not all of them function. In the male flowers (staminate), they still have ovaries and stigma, but they will not function and will abort once flowering is over. However the stamens will usually be longer than the petals and full of pollen, ready for action. The female flower (pistillate) will have stamens, but these tend to be shorter than the petals, and the ovaries are held proud ready for insect pollination.
Yet, even when you have a male and female flower side by side, it can still be tricky as there are many variants within the flower and between the different species and cultivars. Apparently some can change sex; but I don’t want to alarm you as there are no official reports or documents yet, so let’s not complicate things further!
The easiest, most sure-fire way of finding out the sex of your holly is to buy one male and one female. Most species cross-pollinate so you can have a mix of colours and forms. Then, let them get established and nature take its course and, fingers-crossed, you should get berries. This can take a while as hollies are notorious for taking their time. In the interim, you will get lots of superb foliage for your wreaths.
Well, I hope you are blessed with berries and great foliage, as both are needed for the perfect wreath. And please don’t feel guilty if you end up removing the non-flowering plants when you find your ideal holly you’ve been looking for.
Read more about non-berrying plants
Make a Christmas wreath
Find out more about the National Plant Collection of Ilex at RHS Garden Rosemoor