Squirrels and mice
There is no doubt about it: squirrels are a nuisance for any gardener who is fond of their bulbs, particularly in urban areas. Squirrels and other rodents such as mice seem to enjoy Crocus and they may well have a go at Tulip bulbs too.
If you have a problem, there are squirrel deterrents available. Organic chilli sprays and ultrasonic devices seem to be the most popular and effective methods, which can be bought fairly cheaply from a garden centre or online. There are also devices with an infra-red sensor that will spray a jet of water when motion is detected, but these are more expensive. Electronic devices are usually inaudible to humans and pets.
If you don’t wish to use a deterrent, fresh bark chippings can mask the smell of newly planted bulbs but they must be fresh. Also, wire mesh (chicken wire) can be laid over the soil surface, preventing squirrels from digging but allowing the bulb shoots to pass through freely.
Over the past decade, shiny red lily beetles and their ugly larvae have become a real problem for growers of Lilies. These pests like munching on Fritillaria and Cardiocrinum too.
Red lily beetles can be dealt with fairly easily by checking your Lilies regularly. Adult beetles can be plucked off and squashed but be quick as they will soon drop to the ground when disturbed, usually with their legs in the air, making them hard to find. The grubs can also be squashed but as they cover themselves in their own excrement, gloves may be wise! The eggs, found on the undersides of leaves, can be removed and destroyed with a damp cloth.
The majority of bug killers on the market are effective against red lily beetle and many will protect the plant against future attack. Unfortunately, there are no biological deterrents available as yet.