Colour pop: the purple blooms of Iris reticulata Pauline. Photograph: John Glover/Alamy
When I planted my bulbs in September, I held a few back for pots that I moved into the cold frame. The frame offers little more than shelter, but its microclimate is enough to encourage activity during the winter. I keep it chocked open so that air is free to move around it, and only close the lid in the worst of the freeze. Protection is mostly about keeping things dry– the worst of winter damage often comes when things get too wet.
I have always loved bulbs that are willing to tolerate gentle forcing and reward a growth-hungry gardener pining for action in winter. When you are encouraging bulbs to grow that little bit earlier, it is important to acclimatise them so that they do not go from cool to centrally heated in one swift movement. A move into an unheated room or a porch and then on inside after you see them accelerating is the way to go.
The Roman hyacinths were ready to be brought into the house a month ago once their shiny green noses had opened out to reveal the tightly packed buds. Roman and multi-headed hyacinths are lighter on their feet with more air between the flowers than the florists’ type, which can all too easily feel over-bred and heavy. I have had both blue and white in flower for several weeks by bringing a few pots in at a time. Hyacinths and ‘Paperwhite’ narcissus have a powerful perfume which is best kept in a room with plenty of air, for the scent can easily become cloying. A porch or a hallway will allow you to savour them for longer.
A winter feels longer without the illumination of Iris reticulata. If I forget to plant a few I feel like I have failed. A handful of bulbs goes a long way because the delicacy and sculptural nature of the flower needs space around it to be seen at its best. Five bulbs in a 5in pot are about right so that you can scrutinise every line in these delicate flowers. I’ll get two or three varieties and aim to have half a dozen pots that can be brought in over a month or so and staggered.
‘Powerful perfume’: Narcissus Scilly Spring. Photograph: John Glover/Alamy
‘Pauline’ is a beauty: dark dusky purple with few markings. ‘JS Dijt’ is a brighter but equally saturated purple with a bright-gold beard. ‘George’ is a brighter blue. ‘Katharine Hodgkin’ is almost too complex for the garden, but lives up to the scrutiny of pot culture with petals of faded jade contrasted by brilliant freckles. These irises are never good at coming back for a second season in the garden, but the bulbs are cheap enough to discard after flowering.
Bring the iris into a warm room and the buds will grow in front of your eyes before flinging their petals open in a series of jerked movements. I have watched the unfurling happen and you do feel lucky, when all around you is either frozen or sleeping, to bear witness to such willingness to please.
If you do want to try to keep your Iris reticulata in the ground, find a well-drained sunny position and plant deeper than usual – about 6in.