March heralds the beginning of spring, days can be warm and balmy but the weather can also turn wintery, confusing and threatening plants and wildlife. A flurry of shoots, swelling buds and early blossom are the sure signs of new growth. Weeds become apparent and lawns may need their first cut. Drifts of narcissi, both wild and cultivated, dance in the winds, their sunny colours brightening gardens, parks and grassy banks. March brings out frogs and toads from hibernation to frantic mating activity. Breeding takes place in ponds and their deep croaks ring out on warm nights as they seek a mate. Birds too are looking for mates and nesting sites, and fox cubs are born in their hidden earths.
The mild winter weather has continued in February. This can increase the number of predatory insects and plant diseases. Cold weather and heavy frosts kill off pests and pathogens so after a mild winter they can become more prevalent and more damaging to plants as the year progresses. Check over plants early and take preventative methods to protect them from pests and diseases. The mild weather may also deliver early blossoms and bulbs, early amphibian activity and butterflies such as red admirals, emerging from hibernation, seeking nectar on available winter flowering plants.
In the garden
Narcissi are the stars of early spring. A ring of petals, some reflexed or bent backwards, surround a central trumpet. They spread in drifts, covering lawns, borders and open countryside, dancing on slender stalks in the spring breezes. Many are delicately scented; the small white flowers of Narcissi Thalia, Narcissi Silver Chimes, with it’s short, pale yellow trumpet and white petals, Narcissi Minnow, which has pale yellow petals and deeper yellow trumpets and Narcissi Geranium with large cream petals and a short orange trumpet are but a few of the scented varieties.
Early blossoms are beginning to appear against a backdrop of skeletal, leafless deciduous trees. Some cherries flower early, their blossoms appearing before the leaves emerge. Prunus Kursar has deep pink single flowers, Prunus Beni-yutaka with clusters of fragrant pale pink flowers, Prunus cerasifera Nigra, is covered in small, pale pink flowers with a darker eye and Prunus The Bride, with its single white flowers are a selection which flower in March. Magnolia stellata, star magnolia, is lightly scented. It’s large silky buds open to reveal star shaped, multi petalled white flowers. Amelanchier lamarkii or serviceberry, a woodland shrub, has clusters of delicate, star shaped flowers opening just before the bronzed new leaves. Winter hazel, Corylopsis paucifolia has scented, bell like, pale yellow flower on a twiggy frame. These flowering trees and shrubs lift us from winter’s greys with their bright colours and subtle scents.
Many woodland flowers, with their origins in deciduous woodland, take the opportunity to flower early before the leaves of the trees emerge, reducing the levels of light and restricting the growth of understory plants. Leucojum aestivum Gravetye Giant, looking like clumps of tall snowdrop with nodding bell flowers on the tips of the stems. Pulmonarias, which flourish in the shade, often have spotted leaves and flowers from intense blue to murky pinks and even whites. Viola odorata, the native sweet violet, with small purple flowers grows from clumps of bright green, heart shaped leaves. Wood anemones, Anemone nemorosa, and its cultivars, grow from small rhizomes that spread slowly through the rich leaf mould under trees. The white flowers with pale yellow stamens and an underside flushed with violet pink, grow out from filigree leaves with dark, wiry stems.
Sowing hardy seeds
Once weed seedlings start to appear outside, it shows the ground is warm enough for sowing hardy seeds, but you can always start seeds off early in seed trays on windowsills or in a protected environment such as a greenhouse or polytunnel. Many annuals, perennials and herbs can be grown easily from seed and it’s the cheapest way to fill your garden, pots or balcony with plants. Seeds need moisture, warmth and oxygen to germinate; they don’t need fertilizer at this stage of their development. Fill a seed tray, small pot or any recycled container such as a tin or yoghurt pot with drainage holes, with seed or multipurpose compost. For plants that enjoy dryer conditions add some horticultural grit to the mix. Tamp or press the compost down to form a firm surface for the seeds to sit on. Scatter seeds thinly onto the compost, most seeds will need a thin covering, so cover to about the same depth as the seed either with compost or grit. For smaller seeds this is just below the surface, larger seeds may need to be planted more deeply with a wider spacing. Once covered, water the surface well and cover the container with a purpose made lid or a transparent plastic bag. This will retain the moisture and the compost should not need watering again until the seedlings have appeared. Check the seed tray each day and once the seedlings appear, take off the cover. If the cover is left on the seedlings may rot. From now on the seeds will need regular watering, if sunny this may mean more than once a day to prevent the compost drying out. Once the seedlings have two sets of leaves they can be ‘pricked out’, the soil is loosened and they need to be gently lifted, holding onto a leaf not the stem, and potted singly in small pots. They will be vulnerable and may wilt at this stage but careful monitoring for a few days should mean they grow into healthy plants than can be transplanted into larger pots, window boxes or the garden.
Moist soil and warmth are perfect conditions for weeds to start growing. Many other plants will still be below the soil so there is little competition; the weeds like to get a head start. There are many garden weeds but they fall mainly into two sorts - annual weeds, which grow, sow seed and die all within one year and perennial weeds, which are more persistent and come up year after year. These have broad, deep taproots such as dandelion or dock or long string like roots like ground elder or bindweed. They are harder to remove as a new plant can grow from even a small piece of root left in the soil.
Weeding can be done carefully with a hand fork, loosening the soil around annual weeds to pull them out and digging more deeply around perennial weeds, perhaps with a ‘daisy grubber’ to try to get rid of the entire root. Weeds can also be removed with a hoe by pushing the blade against the plant and cutting it off just above the soil. Perennial weeds will not be killed in this way, as the plant will regrow from the remaining root, but over time it will prevent the plant photosynthesizing and it will weaken and eventually die off. Start weeding now and catch them while they are young, it will help later in the spring when the warmer weather encourages faster growth.
At this time of year slugs can have a field day on fresh young leaves, particularly when the weather is warm and humid. As perennials begin to grow, they are particularly vulnerable, slugs may make a meal of them before you have a chance to notice they are there. Hostas, salvias, delphiniums, gerberas, sweet peas, dahlias and many others are at risk. Slugs are soft bodied creatures, they mostly feed at night but their tell tale slime trails indicate their presence.
It is impossible to fully control slugs as so many live in our gardens, however there are many forms of control. Simply going out at night with a torch and picking them off your vulnerable plants works well. Nemaslug, a biological control, which specifically attacks molluscs and does no harm to other creatures, is available to water onto soil. Traps and barriers too can help; an empty half grapefruit skin or a jam jar full of cheap beer and sunk into the soil will attract slugs, these then need to be emptied regularly. Copper tape around pots, crushed eggshell or prickly stems from plants such as brambles form barriers that slugs, with their soft bodies, dislike crossing. Encouraging wildlife of the kind that likes to eat slugs by providing suitable habitat will help control populations. Some birds, frogs and toads, hedgehogs, ground beetles and slow worms all enjoy feeding on slugs.
Early spring is a good time to plant perennials, the staples of the border. There is moisture from winter rains and the soil is beginning to warm up, good conditions for establishing new root growth. Perennials grow quickly, bulking up within a season so buying plants in small pots is economic, 9cm - 2 liter pots are ideal and even plants with only a small amount of top growth showing will soon fill out.
When choosing plants make sure you check the soil and aspect of the site. Is your soil sandy or clayey, is the position sunny or shady? Balconies can be inhospitable with both cold winds and strong sun so make sure you choose robust plants for these. Different plants are adapted to grow well in particular situations and will do less well if put in the wrong place, plant labels and nurseries will give you the information you need to select the right plants for the right place. When choosing to group plants together think about ‘seasons of interest’, choose plants with different flowering times so you have variety throughout the year. Select plants for pollinators, particularly flowers that provide nectar at times of the year when other flowering plants are scarce. Think about a colour scheme, leaf texture and scent.
To plant up an area with perennials first check their mature spread size and then calculate how many plants will be needed to fill each square meter. Some perennials are tall and narrow, some short but spreading, so understanding a plants growth habit is important in determining the gaps to leave between new plants. When you have your plants place them on the soil in their growing position so you can check the spacing and arrangement. Lift pots individually and dig a hole under each, slightly wider than the pot and water into the hole before sprinkling the base with a small amount of a balanced fertilizer. Place the pot in a bucket of water briefly, to ensure the soil is thoroughly moistened, remove the plant from the pot, tease out the roots gently, place in the hole, ensuring the soil in the pot is level with the surrounding soil and firm in all round. When you have finished planting all your plants, water the entire area thoroughly from the top.
The plants will be most vulnerable in their first few months so make sure they are watered if there is no rain and check regularly for pests and diseases. Soon they will be blooming, encouraging wildlife in and giving pleasure.
Feeding, mulching and protecting fruit
Blossoms are beginning to appear, heralding spring and a fruitful autumn. All plants benefit from feeding and mulching and fruiting plants in particular need nutrients to promote flowering and fruit production. To encourage, leaf growth, root growth, flowering and fruiting top dress the soil around fruit trees and bushes with a mixed fertilizer such as blood, fish and bone in early spring. A few weeks later spread 10 cms of well rotted manure around the root area of the plant or tree, being careful not to let it touch the trunk or stem. This will help reduce weeds and competition and reduce evaporation, keeping the soil moist.
Blossoms can be vulnerable both to predation by insects and birds and by late frosts. Cover currant bushes with netting to protect them from hungry bullfinches and use fleece to protect blossoms particularly cherries, apricots and peaches.
Container plant maintenance
You can grow plants in containers even with a very small outdoor space; windowsills, balconies, back yards and patios can all be brightened up with container grown plants. Early spring is a good time to plant containers, warmth and moisture encourage good root growth and plants establish quickly. Add a little slow release fertilizer when planting to feed your plants throughout the growing season.
Early spring is also the right time to repot plants that have outgrown their current container. Carefully extract the plant from its container, remove some of the old compost and tease out the roots, replant in a larger pot with fresh compost in the base and all around the root area.
Maintenance of containers is important throughout the year but particularly from spring and throughout the growing season. Irrigation is an issue in warm weather and pots will begin to need to be checked daily for their water needs. The nutrients in compost are soon used up so pot grown plants rely on regular feeding. Feeding should start in spring when the weather warms up roughly once every two weeks, increasing to once a week if plants are growing vigorously or if the weather is particularly warm. Liquid feeds are easier to use on containers, without over or under feeding. Always check the supplier’s instructions and then watch your plants bloom.
Gardening tasks in March
- Coppice or cut back the stems of cornus and salix to encourage the growth of new, colourful stems for the following winter
- Feed trees and shrubs with a balanced fertilizer such as blood, fish and bone
- Prune hardy evergreen shrubs and topiary
- Plant mixed, native hedging
- Prune bush and climbing roses
- Tie in wall shrubs and climbers as the new growth emerges
- Lift and divide overgrown perennial clumps
- Plant new herbaceous perennials
- Lift and divide large clumps of snowdrops and aconites after the flowers have died but while still ‘in the green’, before the leaves die back. If buying “in the green” ensure the bulbs are cultivated, not foraged from the wild.
- Plant summer flowering bulbs such as gladioli, agapanthus, crocosmias and oriental lilies.
- Sow hardy annuals
- Check soft fruit bushes for aphids
- Check blackcurrants for big bud mite
- Net gooseberries from bullfinches
- Finish any winter pruning of fruit bushes and autumn raspberries
- Feed and mulch fruit trees and bushes
- Protect the blossoms of cherries, apricots and peaches from frost damage with fleece
- Sow alpine strawberries
- Plant melon seeds under cover in the warmth
- Hang bird and bee nesting boxes
- Create rock and log piles for garden wildlife
- Protect new shoots from slugs with organic pellets, crushed eggshells, prickly twigs such as brambles, coffee grounds or beer traps
- Put in stakes of cut hazel or willow to support plants before growth becomes too leggy and floppy
- Hoe and mulch borders to control weeds
- Check pots for watering, if the weather is warm they may begin to dry out
- Top dress pots and containers
Wilding: The Return of Nature to a British Farm
The description of an experiment in what can be done to let nature back into a farmed landscape in Sussex.
Five Seasons of Jam
Seasonal recipes for making jam, jelly, wine and vinegar.
Things to see, places to go
Living Medicine: Self Care Basics
A grounding in self care using food and herbs.
10 March 2019, 10am - 4.30pm
Chelsea Physic Garden, 66 Royal Hospital Road, London SW3 4HS
Explore all things amphibian at the Centre for Wildlife Gardening and pick up a few native plants too.
17 March 2019, 11am - 4pm
Centre for Wildlife Gardening, London SE15 4EE
Spring Plant Fair
Meet growers and select quality plants from 30 specialist nurseries.
22 - 24 March 2019, 10am - 4.30pm
RHS Garden Wisley, Wisley Lane, Woking, Surrey GU23 6QB