Hever Castle in Kent is renowned for many reasons, not least its incredible history and links to Anne Boleyn. It also boasts a beautiful garden with reasons to visit throughout the seasons. Spring starts with a carpet of daffodils, before moving on to a vibrant display of tulips.
Head gardener Neil Miller coordinates the displays, and this year some 40,000 bulbs came into bloom.
Neil says: “We’ve been struggling with squirrels for years and come springtime, there’s always been gaps in our displays. There’s been lots of anecdotal chat from visitors and the team about how to deter squirrels, so we decided to run a trial to see what deterrents there are that might keep the squirrels away
from our tulips. “This was just a small trial to pick up on some of the anecdotal ideas you hear about,” explains Neil.
He explains: “With our huge displays, you can’t put wire over them so it is really about the scent – if you can disguise the smell of the tulip, that’s the thing that will hopefully get the squirrels looking elsewhere."
In autumn 2022, RHS students engaged in their RHS Level 2 Certificate at the gardens worked with Neil and tutor Caroline Halfpenny over six months to uncover the best squirrel deterrents. As the bulbs came into growth, the team checked the tulips daily for squirrel damage.
Here’s what the team tried:
• Apple cider vinegar – dip the bulb in a jar of cider vinegar and plant as normal.
• Chilli powder and chilli flakes – a sprinkle in the planting hole and on the surface. But with anything put on the surface you need to consider that it might get washed away in the rain, or, as Neil adds, with chilli flakes they can end up sprouting if the conditions are right for the seeds that are in the
packet of flakes.
• Peppermint oil – a few drops on the surface.
• Black pepper or garlic powder – sprinkled in and around the planting area.
Other ideas to disguise the smell of tulips:
Grating bars of soap into the planting hole
Grated pungent-smelling moth balls into the planting hole
Tulipa 'Expression' had peppermint oil sprinkled on the surface of the soil, 'Apricot Foxx' was treated to black pepper planted in and around the bulbs, 'Yokohama' was treated to garlic powder on the surface, 'White Mondia' we used peppermint oil on the tulip bulb itself. Tulipa 'Orange' was treated to chilli powder on the bulbs (not surface of the soil).
The trial results
When Hever's tulip displays came in full bloom in April 2023, Neil noted: "The tulips are ALL looking good in the trial beds, which is great news because it means there's a variety of methods that gardeners can employ to keep squirrels from stealing their tulip bulbs!
"But perhaps the best trial bed holds the rather gorgeous egg-shaped Tulipa 'Blushing Apeldoorn' and we treated those bulbs to garlic powder and black pepper mix when we planted them. As the students planted the bulbs, they sprinkled the powder on top of the bulbs, popped the compost on top, then
sprinkled some more on the top of the compost, which seems to have kept the squirrels from picking at them.
"We also believe that underplanting with violas helped so there wasn't bare soil on show and the ground cover helped disguise the bulbs' whereabouts."
“We plant a huge selection for our Tulip Festival," explains Neil. "You’ll find formal displays at the castle entrance, around the castle walls, through the Italian garden and then more natural planting through the longer grass (which is where we plant the bulbs from the previous year’s displays).
"We love to bring different cultivars, everything from the Darwins to the parrot types – it’s a really good mix. New ones to us this year include ‘Ice Cream’ and ‘Ice Cream Banana’, which really does look like a cone of ice cream with the pink at the bottom and then a creamy colour yellow in the middle. Anything a bit unusual that gets the visitor to stop in their tracks and question: ‘Ah, what’s that?’. “It's the colour you can get from a tulip. Daffodils are glorious, don’t get me wrong, but with tulips you get near enough every colour under the rainbow. It’s a bit of a show – and at this time in the garden everything is looking fresh and lovely. The weeds haven’t quite got going and I just want to put my finger on the pause button. It’s perfect."Hever's squirrel problem
Neil says: “We’ve been struggling with squirrels for years and come springtime, there’s always been gaps in our displays. There’s been lots of anecdotal chat from visitors and the team about how to deter squirrels, so we decided to run a trial to see what deterrents there are that might keep the squirrels away
from our tulips. “This was just a small trial to pick up on some of the anecdotal ideas you hear about,” explains Neil.
He explains: “With our huge displays, you can’t put wire over them so it is really about the scent – if you can disguise the smell of the tulip, that’s the thing that will hopefully get the squirrels looking elsewhere."
The trial set up
In autumn 2022, RHS students engaged in their RHS Level 2 Certificate at the gardens worked with Neil and tutor Caroline Halfpenny over six months to uncover the best squirrel deterrents. As the bulbs came into growth, the team checked the tulips daily for squirrel damage.
Here’s what the team tried:
• Apple cider vinegar – dip the bulb in a jar of cider vinegar and plant as normal.
• Chilli powder and chilli flakes – a sprinkle in the planting hole and on the surface. But with anything put on the surface you need to consider that it might get washed away in the rain, or, as Neil adds, with chilli flakes they can end up sprouting if the conditions are right for the seeds that are in the
packet of flakes.
• Peppermint oil – a few drops on the surface.
• Black pepper or garlic powder – sprinkled in and around the planting area.
Other ideas to disguise the smell of tulips:
Grating bars of soap into the planting hole
Grated pungent-smelling moth balls into the planting hole
Tulipa 'Expression' had peppermint oil sprinkled on the surface of the soil, 'Apricot Foxx' was treated to black pepper planted in and around the bulbs, 'Yokohama' was treated to garlic powder on the surface, 'White Mondia' we used peppermint oil on the tulip bulb itself. Tulipa 'Orange' was treated to chilli powder on the bulbs (not surface of the soil).
The trial results
When Hever's tulip displays came in full bloom in April 2023, Neil noted: "The tulips are ALL looking good in the trial beds, which is great news because it means there's a variety of methods that gardeners can employ to keep squirrels from stealing their tulip bulbs!
"But perhaps the best trial bed holds the rather gorgeous egg-shaped Tulipa 'Blushing Apeldoorn' and we treated those bulbs to garlic powder and black pepper mix when we planted them. As the students planted the bulbs, they sprinkled the powder on top of the bulbs, popped the compost on top, then
sprinkled some more on the top of the compost, which seems to have kept the squirrels from picking at them.
"We also believe that underplanting with violas helped so there wasn't bare soil on show and the ground cover helped disguise the bulbs' whereabouts."
So there you have it: a black pepper and garlic powder mix, plus underplanting with violas, could be the best solution to keeping squirrels from your tulip bulbs.
Here's more on how to grow tulips