Planting bulbs

Where should I buy spring-flowering bulbs?

Always ensure bulbs are healthy and fresh. Stock in supermarkets or DIY chains, while cheap, might have been “hanging around” for weeks. Go to a reputable garden centre and look for plump, firm bulbs. Buy them early to make sure you get the best stock.

How do I plant bulbs?

If you intend to lift them after flowering, plant them in a hole that is around twice their height, spacing them two bulb widths apart. On wet land, put a thin layer of sand in the hole. Always plant them with their tops facing upwards. Break down large soil clumps before covering the bulbs, making sure there are no air spaces around them.

What are naturalised bulbs?

Bulbs left in the ground year-round are said to be “naturalised”. They are planted deeply in holes three times the bulb’s height, so as to avoid disturbance by other cultivations.

When can I move spring bulbs?

While we buy and plant bulbs when they are fully dormant, if you just want to transplant them in your garden, they can be easily moved before they die down. The advantage of doing this is that they are easier to locate and can be replanted at the correct depth. Just wait until foliage starts to turn yellow before you move them.

garden tulips in pots

Tulips planted in pots create a colourful display. Enjoy more of this tulip filled garden

Last year I was given some potted bulbs that have since died down. Can these be planted in the garden?

In short, as long as they are hardy, yes. Obviously it will pay to check whether they are suitable, as some, such as large-flowered hippeastrum (amaryllis), are frost-tender and must be grown indoors. “Forced” Christmas bulbs, such as narcissi and hyacinths, can easily be naturalised, but may take a couple of years to flower again.

Is June the best time to lift spring bulbs or can I wait until autumn?

While June is a good time to dig up spring-flowering bulbs, it is restricted to early bloomers, such as daffodils. These can be lifted around six weeks after they finish blooming, by which time the foliage will have died back. The simple rule of thumb, though, is that if it hasn’t done so, then wait longer so as to let the bulb build up some food reserves. Don’t delay too long, however, as the withering foliage means you can still see where they are growing; there is less of a chance of damaging them if they can be easily found. Later-blooming bulbs will have to wait a bit longer, whereas hardy, summer-flowering bulbs, such as lilies, should be dug, moved and replanted in early autumn.

Why is it best to wait until November to plant tulip bulbs?

Tulips are planted late (mid to late autumn) as this helps to reduce problems with tulip fire – a fungal disease that causes new leaves to become distorted or twisted. Affected plants become brown and wither – essentially as if they have been ‘scorched’. When planting tulips, avoid crowding them, spacing at least twice the bulb’s width apart and at a depth of two or three times the bulb’s height. Ensure the (pointed) tip points upward and the (flat) base plate faces down.

garden with bench tress and shrubs

Prune trees and shrubs with care. See more of this wildlife friendly garden on the Isle of Wight

Pruning plants and shrubs

I want to get out into the garden and do some pruning. How should I start?

Before you begin pruning plants in the garden, it is important that you first establish what you hope to achieve. Cutting back a plant without a plan can easily result in ‘mutilation’, so avoid just charging in like the proverbial bull in a china shop!

Start by finding out what the plant actually is. Many species have specific requirements about how and when they can be pruned. If you do your research first, it will give better results through the next season.

If you are unable to identify the specific species of plant, simply remove any dead, dying, damaged or diseased wood, as this helps to keep the plant healthy. Lightly shape the plant afterwards to maintain its overall balance.

What tools will I need?

The basic minimum is a good pair of sharp secateurs and a pruning saw. Secateurs come in many forms; the bypass (parrot-beaked) variety is my personal ‘weapon of choice’. Small, foldable pruning saws are ideal, as they can be stored safely when not in use. Use loppers for thicker branches and to work among thorny shrubs.

What else will I need?

Before starting, get yourself a book on pruning, as knowledge of a plant’s pruning requirements is really important. In most cases you won’t need much equipment. A plan of action is much more effective than a tool shed full of fancy kit when it comes to this job.

Should I cut off the dead flower heads on my garden plants?

There are no absolutes where this is concerned, just rules of thumb. In the main, most summer-flowering plants can benefit from deadheading, as it encourages repeat flowering if done regularly. Others flower only seasonally, though, and so no amount of cutting will overcome this. The heads only need removing to prevent self-seeding. However, most of the summer bedding plants and a good number of hardy perennials can have their flowering period extended in this way. Simply remove the flowers as they start to fade and remember to feed them regularly with a liquid feed rich in potassium (such as tomato food) to encourage more buds.

daphe odora Rebecca plant with purple flowers

Find out some of the experts’ choice of plants for traditional gardens

Planting bare-root trees

What are bare-root plants?

Many trees, shrubs and, very occasionally, herbaceous plants, are supplied as bare-root stock. This simply means that the plant has been lifted without soil around the roots, making it lighter to transport and easy to handle. The roots are, however, very prone to drying out until they are once again re-planted.

Are bare-root shrubs difficult to plant?

They are relatively easy to plant. Dig a hole big enough to fit the roots without any touching the sides. If you need to stake the plant, hammer it into place before filling the hole, moving the plant to one side to avoid damaging it. Refill the hole with the excavated soil, firming it in layers of 10–15cm as you go.

When is the best time to plant bare-root stock?

Any time between December and late February, although do not attempt it if the ground is frozen or waterlogged. Planting in mid-winter gives the roots more time to re-establish, resulting in a healthier, more drought-resistant plant the following summer.

What sort of aftercare do they require?

Protect newly planted bare-root stock for the rest of the winter until established. Cold winds and frosts can loosen and lift the roots, so check and re-firm them in if this happens. Keep the soil around the base completely weed free, as these compete for space, water and nutrients in the early stages.

garden in winter

Topiary and box hedging provides structure and interest in this frosty winter garden

Caring for plants in winter

What plants need protecting over winter?

Increasingly, gardeners have used exotic looking plants to create lush, tropical effects in the garden. While some of these are perfectly hardy, others – such as dahlia, canna lily and Japanese banana – are severely damaged or even killed by frost. If you grow these, then they usually need protection to help them through.

Do I need any specialist items or equipment to protect my tender plants?

You can buy materials such as horticultural fleece or hessian, but bracken, dry leaves or straw can also be used to insulate plants from cold or wind. Fleece has the advantage of being breathable, which reduces the possibility of rot.

Polythene should only be used as a “roof” to prevent the entry of water. Ideally protective covers should be removed during spells of mild weather but replaced as necessary. Pots should also be protected. Bubble wrap is ideal for this and can be used as extra insulation in very cold spells. You can buy it from most DIY centres.

How do I wrap plants growing in the ground?

Place a rigid frame or wigwam of bamboo canes around plants, and then lightly pack with dry bracken or straw. Secure it with netting or fleece. Surround large plants with a double layer of wire netting enclosing a 5–7.5cm layer of bracken or straw. Put a waterproof lid over structures to keep packing materials dry.

garden vegetables

Grow seedlings in a greenhouse or warm environment before planting out. Create a beautiful and bountiful kitchen garden by following our guide

Raising plants from seedlings

Can I raise seeds of tender plants inside if I don’t have a greenhouse?

If you have a warm room, ideally around 21-25°C (70-77°F), and a windowsill with bright – not direct – sunlight, then this can be a good place to raise seeds. If the room is unheated or cool, you can get a small heated propagator to maintain the right temperature for raising the plants.

What does it mean when a packet says to ‘harden off’ plants before planting them out?

Hardening off simply means acclimatising the young plants to the harsher conditions they will encounter outdoors. It involves a gradual process, such as opening greenhouse vents (or the
window if growing indoors) during the day, but protecting them from night-time chill until it is warm enough to put them outside.

Moving and dividing plants

Can I use the plants I had for spring bedding elsewhere in the garden?

Many of the plants that we use for spring bedding are perennials and can make useful fillers. The best candidates for reuse are primula (primroses and polyanthus) and erysimum (wallflowers), as both are relatively robust and long lived. Cut the latter back hard to encourage regrowth after transplanting.

What is the best method for lifting and dividing plants?

Lift whole clumps gently with a garden fork, working from the outside and getting the fork tines under the crown to limit root damage. Shake off any excess soil to expose the roots. Some species can be prised apart easily to produce smaller clumps, or even individual plants, whereas others will need a more vigorous or forcible approach. Fibrous-rooted or densely ‘clumped’ specimens can be split by inserting two garden forks, back to back into the middle of the crown, then using these as levers. Plants that have woody crowns or fleshy roots may need cutting – using a spade or knife – into clumps containing three to five shoots. Be sure to then water these clumps well once replanted.

garden with beds of roses

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Digging and fertilising a garden

Why is it important to dig the soil, and when should I do it?

Digging is a way of incorporating organic matter deep into the soil, while bringing up well-rotted matter (humus) to the surface. When done regularly, digging encourages the rapid cycling of nutrients available for plant growth, while also creating a soil consistency that is easy to work with.

When to dig the soil will depend upon what you want to do with the ground and the soil type in your garden. Heavy (clay) soils should be dug before the coldest part of the winter, so as to enable frost to penetrate and to break up any clods. This will make for easier cultivation come the spring. Light (sandy) soils, on the other hand, are best left until spring, if dug at all.

Do I need to add manure or compost?

Adding organic matter is always a good idea, particularly on lighter soil, where it will help with water retention later. Many gardeners simply spread organic matter over the surface of the soil and allow natural processes to work on it – a method called no-dig gardening.

Should I mulch the ground that I am not going to dig now?

If the weather is mild, possibly – but applying mulch in the coldest months can simply seal in the cold for a protracted period. It is best to apply mulch as growth commences, ideally using a 50mm layer of well-rotted material. Do not cover the newly emerging plants as these can then rot.

Looking after your lawn

When should I feed my lawn?

Spring is the perfect time to feed a lawn, but be sure to use a proprietary high-nitrogen spring lawn fertiliser. This is different from mixtures used in autumn, and it will encourage good, strong growth. Apply it at the beginning of the month as growth commences. Many available brands are combined with weed and mosskiller.

What can I do to stop my lawn becoming covered in weeds?

After the rigours of winter, weeds often get a head start on the grass, and can become a problem in ornamental lawns. April is the best month to apply lawn weedkiller, as the grass plants will rapidly grow into gaps left by the dead weeds. Use a reputable brand and always follow the instructions to the letter for best results.

How is it best to compost lawn clippings? 

If you just make a pile of your clippings, they become rather smelly and slimy – a product that can prove toxic to plants and soil life. To avoid this, add the clippings to a compost heap in thin layers, interspersed with other material. Avoid using clippings treated with herbicides, though, as these can affect plants when returned as compost.

Should I water the lawn as it gets warmer?

Newly established lawns can be watered in their first year. After this, it is better to aerate the ground in early April, as this encourages deeper rooting. Towards the latter part of the month, raise the cutting height of your lawnmower, as keeping your lawn a little longer slows its growth and improves its drought resistance.

garden lawn

The immaculate lawn of this garden in Sussex has been carefully tended. Find out how the owners created their garden full of colour and interest

Houseplants and pots

Do my houseplants need any special care while they are outdoors during summer?

Plants matched to their preferred situation (i.e. sun or shade) generally respond well to their ‘summer break’. Remember, however, that they are likely to be much thirstier while outside, with any rain unlikely to be sufficient for their needs. Therefore, water them at least once a day if it is hot, and feed them regularly to promote strong growth.

Should I move houseplants outside during the summer months?

Many indoor plants, especially those in conservatories, benefit from being placed outside for the summer between July and early September. In most cases, they need to be placed in a sheltered position to prevent wind damage. Also be prepared to cover them with garden fleece, or bring the plants back inside if a cold night is threatened.

How can I keep my potted plants healthy in hot weather?

Summer heat can prove as challenging to indoor plants as the cooler winter months. If they are in a greenhouse, open the vents wide in the daytime and dampen the paths and benches on hot days. This will help to cool them but also increases humidity, something that will deter pests such as red spider mites. Smaller greenhouses may also benefit from a coating of ‘shade paint’. If you have plants in the house, then move them somewhere where they will be out of direct light through the hottest part of the day, and mist them with a small hand-sprayer two to three times daily.

garden expert Mick Lavelle

Mick Lavelle is a gardening writer and senior lecturer in horticulture at Writtle University college