e-mail Jane Owen with your gardening questions: jane.owen1@timesonline.co.uk

Winter flowers. How can I get interest through winter? I am not interested in evergreen shapes. Sarah Stanley via e-mail

Lots of exquisite iris flower during winter. My favourite is Iris stylosa which has had its name changed to something ugly so I will not use it. I have seen its beautiful, fragile blue appearing in snow. Cyclamen coum will thrive in the tricky area under trees and give you both exquisite marbled leaves and dainty white or pink flowers. Various Daphnes and Viburnums will give you scent as well as flowers, as will winter honey suckle although it is a wretched looking shrub. Wintersweet (Chimonanthus) with its curious waxy yellow flowers with a deep red centre, witch hazel and Mahonia are good winter shrubs with highly scented flowers. Snowdrops, grape hyacinths and winter aconites never fail to please. Winter jasmine is a yellow flowered bush which was put on this earth to set my teeth on edge but you may like it. Hellebores are God’s own flowers despite the fact that they have no scent to speak of. Their voluptuous blooms range from the classic white of a Christmas rose to the deep reds and almost black and they breed with abandon once established, bringing forth deliciously multicoloured children

I saw on Gardeners World green roofs. How do you make them? I don’t mean the construction which I can do. It’s the plants. Reg Beckman Via email

You can buy a range of plants like sedum which will survive periods of drought followed by heavy rain but it’s probably easier to buy a custom-made roll of planting – rather like a roll of turf for your lawn. You can buy this from various sites like this one from Greenroof or this www.qlawns.co.uk just follow the instructions to the letter.

What gardens are worth visiting at this time of year? We have garden-mad friends coming to stay this weekend and we’re hoping for good weather. Jan Surridge, Norwich

Your question brings back unwelcome memories of filming in the tipping rain, in November, for the Gardens Through Time BBC 2 series. We were filming at Pensthorpe nature reserve in Norfolk which has gardens designed by Piet Oudolf and Judy Toll. Even in November the gardens looked beautiful and so I’m sure they would at this time of year. And, if it rains while you are there, think of me having to do pieces to camera while the crew feasted on bacon butties and cups of tea in the cosy shelter of the thatched hut at the centre of the garden.

Another garden in your area, which should still be looking good now, is Bressingham. Like Pensthorpe the planting is based heavily on grasses which is not usually to my taste but these gardens show grasses at their best.

Finally, The National Gardens Scheme charity has an excellent website locating gardens to visit by time of year and location with one area dedicated to eastern England.

The whole of the wall on the south of our house has been covered in ladybirds for a few days and they are now coming into the house. I wouldn’t normally mind but I have heard that there is a new type that is bad for our gardens in some way. Is that so and how should I deal with them, please Jane? Leyla Shilton via e-mail

Non-native species or harlequin ladybird Harmonia axyridis have invaded from Asia and they are excellent for gardens in the sense that they have a voracious appetite for aphids and other baddies. The problem is that they have such voracious appetites that there is nothing left for the native species. They (the natives) then die of starvation. The invaders are slightly larger than natives and they come in a wide variety of colour schemes - these pictures from the BBC website might help confirm whether or not your ladybirds are invaders

You might also like to let the following website know about your ladybirds – the website is recording the invasion so at least the demise of yet another species will be recorded. More seriously, I do not know how the invasion will be stopped

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