It may seem an odd time of year to be talking about growing for butterflies, as they are staring to pack their bags for another year - don’t panic – the winter is not quite upon us yet, but with all gardening it pays to think ahead. When you are planting anything expected to last more than one season then the autumn is a great time to do it – so now you are back from your holidays, it’s time to start thinking about next year’s flowers.
Butterflies, like so many of our insects, are under increasing threat from pesticides and loss of habitat. They will visit any garden and we have the opportunity to attract up 20 species if we work at it! There are a number of plants that will help to attract butterflies but location is nearly as important as plant selection. When planning a butterfly “patch”, pick a sunny sheltered spot, and plant a number of each plant variety in blocks. Nectar across the season is vital for butterflies, especially in the leaner, spring months, as these are key for butterflies coming out of hibernation. Autumn flowers are key for building up their strength for getting through the winter.
Prolong flowering by dead-heading regularly and watering well as necessary. Water is especially essential for nectar production. Avoid insecticides as much as you can – completely if possible. Butterflies are delicate and very susceptible to chemicals.
Caterpillars are also key of course, and there are some amazing looking beasts that come under this heading. I will cover how to encourage these and moths, which are so key to pollination of many species, next month.
The list of plants is fairly long and the RHS publish a list on the Internet, as do many butterfly conservation sites. Spring nectar producers for butterflies include early Buddleia varieties, Hebe, Honesty, polyanthus and violets. The end of season favourites include ivy (also important for bees), michaelmas daisies and sedum spectabile (beware of non-nectar producing varieties).
You can target specific species – in which case best to look up their favourite food on the Internet. The “top 5” for a wide variety of butterflies are usually quoted as follows:
Buddleia (The butterfly bush) - easy to grow in almost any soil. Different varieties will flower in pink, red, purple, and white. Usually in bloom through July and August. Several varieties, including the 'basic' Buddelia davidii, the yellow pompoms of Buddleia globosa, and the hybrid of the two, Buddleia x weyeriana. The lilac buddleias are said to be best and these are an absolute favourite with 18 species including Brimstone, Comma, Common Blue, Gatekeeper, Green-veined White, Holly Blue, Large Skipper, Large White, Meadow Brown, Painted Lady, Peacock, Red Admiral, Small Copper, Small Skipper, Small Tortoiseshell, Small White, Speckled Wood and Wall Brown.
Verbena Bonariensis - stems up to a metre tall support heads of lavender coloured flowers from August to October. Easy to grow from seed, plant March-April in well-drained soil. Can provide useful height at the back of a border.
Lavender - lilac-blue flowers grow on spikes through the summer. Plants can be used for edging beds or grown to form an attractive, low-growing hedge. Needs a sunny, sheltered position in well-drained soil. Lavender should be planted in April or May and pruned back to encourage bushy growth.
Perennial Wallflower (Bowles Mauve) - produces a profusion of sweet-scented purple flowers from April all through the summer. Wallflowers make great bedding plants and will grow well in full sun or light shade. Plant in well drained soil.
Marjoram (Oregano) - a perennial herb, growing from 20 to 80 cm tall. White, pink or purple flowers grow on spikes from June to September. A good edging plant and useful ground cover, requiring little maintenance. The smaller varieties also do well in rock and alpine gardens.
In the May edition, I made some recommendations about avoiding, or at least reducing the chances of getting, pests and diseases. The “prevention is better than cure” model! In the second part I will talk about some useful methods of Wildlife-friendly pest control. We want to adopt a “live and let live” approach where we can, but sometimes we have to take matters into our own hands, when the garden is subject to unacceptable levels of pest damage. Ideally we do this whilst still avoiding harming the environment and specifically beneficial members of the animal kingdom.
There are a number of key weapons in our armoury to prevent pest damage – at the top of the list - barriers. Covering your vegetables with a fine mesh you will stop them being attacked by flying pests.. Fine mesh over brassicas is recommended to protect from a number of flying insects, and birds of course. Other barriers include cabbage collars and bottle cloches. Placing a collar of carpet underlay around the neck of a young cabbage will prevent the cabbage root fly from laying its eggs at the base.
Placing a bottle cloche, a clear plastic drinks bottle with the top and bottom removed, over newly planted vegetables will prevent them being eaten by slugs or anything else that takes a fancy to them. Small gauge chicken-wire is useful over newly sown peas to protect from mice, or wrap it around your flowering bulbs to prevent squirrels from digging them up.
Slugs are most people's worst enemy, and I have spotted a few giants this year – Spanish perhaps? They don’t deserve to win the World Cup! Barriers of anything sharp and gritty are supposed to protect your tender plants, as is bran (apparently they eat it and dehydrate). There are all sorts of products available for slug control on the organic market now. One that springs to mind is a band of copper that gives the slugs electric shocks – works around pots. Copper mats, thick layers of crushed eggshells and even coffee grounds can deter them. If using a barrier method with slugs remember that success depends on being extremely liberal with the chosen deterrent and topping up after rain.
You can kill slugs without harming hedgehogs or slow worms by luring them to their death using beer traps. Ensure the traps are proud of the soil so beneficial ground beetles don’t fall in. Please try to avoid using slug pellets as the dead slugs and snails get ingested by wildlife and will harm or kill these gardeners’ friends. Use wildlife-friendly alternatives to slug pellets (see above), or if you have to use pellets, choose ones which don’t contain metaldehyde and pick up dead slugs and snails as soon as possible.
Of course birds love slugs and snails – especially thrushes – so put food out for them and provide nesting sites. Fruit is a favourite of thrushes and blackbirds. Scatter over-ripe apples, raisins and song-bird mixes on the ground for them. To make your garden an attractive place for thrushes to live consider planting berry-licious shrubs and trees, including favourites like Malus, Sorbus, Cotoneaster and Pyracantha. If you have room, a pond (even a very small pond) is useful for keeping pest numbers down. It will encourage frogs (which eat slugs) and bats (which eat mosquitoes and other flying insects). Nematodes naturally kill pests such as slugs and vine weevil, without poisoning the soil or harming other wildlife, but they have a short shelf-life and can be expensive.
There are a couple of specific pests worth mentioning for Tatsfield gardeners. Deer can decimate trees and do serious damage to roses (Roe and Muntjac love roses). You can buy deterrents but these tend to lose their effectiveness in the rain. Human hair in an old stocking hung around a tree or in amongst the roses actually works better after rain. It really does work – try asking the local barber for a bag of hair! I suggest you handle it with rubber gloves though! Mice can be a right pain with vegetable seeds – especially beans and courgettes. If you don’t want to be involved with waging an unpleasant war involving traps, then plant the seeds indoors and only plant out once the plants are well under way.
Good luck with the growing – and may all your pests be little ones!