I’ve always found tulips easy to grow, but the bulbs I planted last autumn haven’t done well. When the plants first appeared above ground earlier this spring, they looked okay. But as they’ve grown and started to flower, dirty grey-brown patches have appeared on a lot of the leaves. Even the flowers themselves aren’t properly developing, and are dying off before they’ve fully opened. Is this the dreaded tulip fire disease, do you think?
Claire, Co Galway
I’m afraid that you’re almost certainly correct in suspecting tulip fire (Botrytis tulipae), a very destructive fungal disease that has unfortunately become common in Irish gardens in recent years. Easily brought into a garden accidentally by infected bulbs or even just infected flowers, it’s activated by damp, humid weather and then spread via microscopic fungal spores as well as by seed-like “sclerotia” that initially appear on infected plant tissue. A wet spring exacerbates the symptoms, allowing the disease to hop easily from plant to plant. Planting the bulbs closely together, as is so very often done with tulip bulbs to create impact, also encourages its spread.
The bad news is that the only remedy for tulip fire is to dig up all infected plants along with their underground bulbs, and to then carefully dispose of them off site. Even then, this fungal disease can persist in the soil for at least three years, with the risk of reinfection if any diseased plant material is inadvertently left in or on the ground or added to the compost heap. For this reason, even infected flower petals that have fallen on the ground should be bagged and binned.
RM Block
To minimise the risks of reintroducing this disease into your garden once the standard minimum quarantine period of three years has come to an end, make sure to only use fresh, healthy-looking bulbs sourced from a reputable supplier, and to avoid bargain-basement bulb sales, or any dubious online suppliers. It’s also important to hold off planting these spring-flowering bulbs until November, as the cooler soil temperatures at that late time of year help to prevent the disease from becoming established. Deep planting, to a minimum depth of 15cm, also discourages the disease.
[ Tulips: the flowers that get on with almost everything else in the gardenOpens in new window ]
If you can’t just bear the thought of going entirely without tulips for so long, try growing them in containers in the meantime, using fresh, bagged compost or topsoil each year bought from a garden centre to do as much as you can to ensure it’s disease-free.
