Just before the main flush of new spring growth gets going is the perfect time to divide herbaceous perennials to maintain their vigour and create new plants for your garden. Identify suitable large clumps and those which are becoming donut shaped with a dead centre. Lift with a fork working around and under the plant until you can lift it whole easily. Shake of some of the soil so you can see the roots. If they are small and fibrous (like asters) they can be eased apart with your hands into new clumps. Those with chunky roots (like day-lilies) will need to be levered apart with two forks back to back inserted into the centre of the clump. Those with woody crowns (like irises) need a spade or sharp knife to split them. Always identify the new shoots and make sure each of the new sections have at least 3 or 4. It's important to replant quickly. You may replace a clump in the original location or in new locations or somewhere where you can "heel them in" to store them in the ground to be sited at a later date. Some could also be potted up or kept in large trays with fresh compost to grow on and establish. Just remember to water in all the divisions thoroughly and keep an eye on them as they re-establish.

Now is the perfect time to take basal cuttings from any perennial that makes multiple stems from one crown, such as Delphiniums and Lupins. Scrape the soil away from the base of the plant, then with a sharp knife carefully cut away new shoots approx 8-10 cm in length close to the crown. At this stage of growth basal stems are solid whereas later they become hollow and then they will rot rather than root. Fill a 1 litre pot with a gritty, loam-based compost and insert up to 5 cuttings, evenly spaced, around the edge. Water in, cover the tops with a clear polythene bag and place in a cold frame. At the first sight of the roots at the bottom (probably in 4-5 weeks) transplant the cuttings into individual pots. Harden them off before planting out later in the season.

Some of the key tasks this month are... winter pruning wisteria and cutting back other climbers such as ivy and Virginia creeper; pruning hybrid tea, floribunda, shrub and climbing roses; pruning late-summer flowering (Group 3) clematis back to the lowest pair of strong buds; pruning last years growth from perennials such as Sedum and Acanthus (but wait and don't prune Salvias yet!); prune deciduous late-flowering shrubs such as Buddleija davidii, hardy Fuchsias, Lavatera; and pruning autumn flowering raspberries (cut all stems down to the base) and blackcurrants (cut out up to a third of the oldest stems down at the base). 

The benefit of cutting back stemless hellebores (such as Helleborus × hybridus varieties) right at the base, is to maintain optimal plant health preventing hellebore leaf spot disease being carried through the winter to infect the new leaves. Removing the old foliage also means the flowers can be seen and enjoyed better. At the same time, it's a good idea to mulch around them with compost. Don't prune Helleborus foetidus in this way however, as they flower on thick stems just above the tops of the foliage. You'll be able to see the buds now so you'll know just by looking not to prune these.

You can definitely put your feet up for Christmas if you've finished mulching your beds and borders! Applying a generous layer is really important to avoid leaving bare soil over the winter, as rain can wash away soil nutrients and even the soil itself. It will also shield plant roots and crowns from freeze/thaw cycles and possible damage from cold. Just don't pile it up might against plant crowns or stems, as this can cause rotting. I've been using the time (and money!) saving approach of "chop and drop" more this year. Just shear back perennials into small clippings and leave them on the ground at the base of the plants rather than clearing to compost or the green waste bin. Just spread the material out evenly on the soil surface to break down naturally. It just doesn't work with anything slimy like Hostas and Agapanthus which will need removing.

Bare root roses will start to be delivered around now and it's a great time to plant them. First hydrate the rose fully by immersing in a bucket of water for at least 4 hours (I usually do this overnight). Prepare the soil by forking over and removing any weeds before digging a hole which is at least 40cm wide and a similar depth. Roses are gross feeders so after forking over the bottom of the hole, it's good to add plenty of organic matter and maybe something like blood, fish and bone or similar organic fertiliser. Next, I always cover the wet root system with Mycorrhizal Fungi by shaking over the roots in a plastic bag before putting the rose into the hole and spreading the roots out well. Placing a bamboo cane across the top of the hole gives the right level for planting and the graft union (the swollen part on the stem) should be just below the cane, i.e. just below the soil surface, and not proud of it. Then backfill the soil, heel in firmly and give it plenty of water. Job done!

This is the month to begin winter-pruning deciduous trees and shrubs. Focus on taking out dead, diseased and damaged wood and for established shrubs consider removing up to a third of the oldest wood completely leaving an open structure as far as possible. Don't be tempted just to "round off" the growth to the height you feel looks best, this won't produce the best shape or flowering potential. Autumn pruning is essential for Japanese maples to avoid excessive bleeding of sap from pruning cuts which could occur in the spring when the sap is rising. There are however two don'ts - don't prune off next year's flowers by pruning those shrubs which will be coming into flower over the winter and into spring. eg Viburnum x bodnantense or Forsythia for example; and don't prune ornamental cherries (Prunus) which are done in summer to avoid risk of the fungal disease Sliver Leaf.

Things I've learned to make hedge cutting easier! 1.) Check how it's growing before you start, it's probably not uniform so this needs to be factored in if you want straight sides/top. 2.) Clear your work area of obstacles and lay out tarpaulin or sheets where you can to catch the trimmings. 3.) Set up a string line on stakes along the length of the hedge about 1cm below the height you want to ensure you achieve a straight top. 4.) Do the sides first working with sweeping cutting arcs from the bottom up. Trim lightly to start with to make sure you've "got your eye in" 4.) Leave the hedge wider at the bottom than the top, never the other way round. 5.) Finish with the top and keep checking your progress by regularly stepping away and taking a look.

This month is about your approach to perennials coming to the end of their season. A really good idea I think is "de-browning" - that is removing any petals that are browned off rather than removing the whole flower. Dealing with Rudbeckia this way is really effective and you'll be surprised how this keeps the remaining flowers looking so much better. A good rule of thumb is "if it's standing - keep it, if it's fallen - remove it". So I remove any mushy leaves but importantly I'm looking to retain any with autumn colour or with lovely seedheads, many of which come in a range of eye-catching shapes and textures. Beautiful when covered with frost, they also provide food and shelter for wildlife during the winter. Particularly lovely are Phlomis russeliana, Lunaria annuua, Veronia arkansana, Eryngium gigantea and Echinops ritro

With mild and damp conditions this is good month for lawn maintenance. Scarifying with a spring-tined rake (or power scarifier) will remove built up thatch to improve air-circulation and help prevent fungal problems. Using a hollow-tine aerator (or a garden fork) to create spikes 15cm deep at regular intervals will also help get oxygen to the roots of the grass. I top dress with a simple mix of fresh top-soil, sand and organic matter to fill the aeration holes. I see the RHS recommend this in the ratio of 3:6:1. There's still time for new grass seed to establish if sown on bare/worn areas. Finally if feeding make sure you use an autumn lawn feed which encourages root growth through winter, rather than leafy growth. 

September is a great month for planting! Now is the time to start putting in bulbs for daffodils, crocus and hyacinth, but also trees, shrubs and many hardy perennials. The soil is in a perfect condition, and whilst there is still warmth and moisture your new planting will have time to settle and establish a good root system before the harsher winter months arrive. Autumn rainfall should mean it's easier to keep newly planted trees and shrubs watered as they establish too.

Late summer is the time to trim your lavender, just after it's finished flowering. Go over with the shears removing the flower spikes and around 2-3cm of the leafy growth encouraging the plants to put out side-shoots, keeping them bushy. Not trimming them back risks the plants becoming leggy - and you won't be able to renovate them later by cutting back into stems which have turned woody as they won't regenerate 

Start taking ripening seed by snipping off the dry brown heads of perennials or annuals - keep them in paper bags or envelopes to dry and store. Take cuttings from tender perennials like fuchsias, penstemons and pelargoniums. It's also a good time to start planning and ordering spring bulbs - yes I've ordered some already!!

Top things to do if you're leaving your garden to go on holiday... get up to date deadheading repeat-flowering plants like roses, cosmos, dahlias, pelargoniums, annuals... group your pots somewhere in the shade to reduce them drying out... empty your water-butts (it'll be raining back home and will fill them up again!)... and if you've time - do some weeding so you don't have so much to come back to. Happy hols!

There's lots of opportunities to take softwood and semi-ripe cuttings from shrubs now. Propagation is one of the joys of gardening! You need to take non-flowering shoots to produce cuttings about 8-10 cm long. Sterilise your secateurs or knife with then cut just below a node, reduce the number of leaves to 2-4 and cut those remaining in half. A 1 litre pot with a potting media mix of 50-50 peat-free compost and perlite is ideal for 5 cuttings with a polythene bag over the top to maintain humidity. Keep in sheltered spot out of direct sunshine. Hopefully in 6-8 weeks they may be ready for potting off.

Time to prune late-Spring flowering deciduous shrubs such as weigela, deutzia and philadelphus. Concentrate on removing any dead or damaged growth and then selecting the oldest branches to remove, all the while considering how you can create the best shape and form. Looking up and out from the ground on the inside of very large shrubs if you can is always a good viewpoint when considering pruning. If in any doubt it's best to use a pruning saw to cut thicker branches - don't strain your secateurs and loppers.

With mowing season in full swing now - vary the direction of your cuts each time you mow so stop grass blade growing in the same direction and reducing the effectiveness of you cut. Now is a good time to add a liquid fertiliser feed which will buck the lawn up if looking a bit tired. Don't forget the edging it'll make all the difference to the finished look. Finally, take care dumping grass clippings on the compost - add some woody material or torn up cardboard/paper to make sure there's enough air in the mix or it risks ending up a slimy mess.

Time to prune the early flowering shrubs once they've finished like Forsythia, Kerria and Spirea, and tidying up Choisyas to remove any dying foliage or to shape and maintain within it's allocated space. Also good to trim Aubretia to stop it looking bare and tatty

First job in May for me is usually one I've always run out of time for in April - sowing dwarf and French Beans 5cm deep in deep pots and if the weather is warm like it is now the greenhouse is fine for them to germinate, otherwise I use a bottom-heat mat under a propagator. I'm also continuing succession sowing of various lettuce and salad leaves in troughs and have just potted on my sweet red pepper seedlings which should start growing more strongly now in the greenhouse.

Taking basal cuttings is a great way to increase your stock of perennials like lupins, delphiniums and achillea. Just take a clean sharp knife and cut away some of the new growth that shoots up at the edges of the  crown. Remove the material at or just below ground level so you take a small part of the previous year's growth as well. Plant the cuttings in new, dampened compost and cover with a clear bag for a few days to reduce transpiration loss. Your cutting should root in 4-6 weeks and be ready to plant in a couple of months time. Just protect from slugs and snails!

First job is to start getting borders tidied up - using a border fork to lightly break up the soil surface pulling out any weeds. The important thing is to watch out for self-sown seedlings. You may wish to move some of these about a bit, particularly foxgloves (Digitalis) as they often need a bit of editing I think. I also like to finish deadheading daffodils. If the spent flowers are left on the energy will be diverted into making seed rather than forming next years flower bud within the bulb. Whether you snap off or snip off the developing seedheads from the stalk is up to you - everyone has their preference!

This is the month to move any evergreen shrubs now the soil is warming up. They will shortly begin to grow strongly and won't find it so hard to replace lost water, which is why it's not a good idea to move them in winter. It's also a perfect time to divide congested clumps of summer flowering perennials, and Hostas, enabling them to grow with renewed vigour and giving you additional plants for free. Any plants with new growth round the edge of a clump with a dead, dry centre definitely need dividing. Water and mulch generously after.

Time to start regular lawn care. A traditional British lawn would be a mix of bents and fescue and in March, depending on the weather, 2-4 cuts would be what we're aiming for with a sward height of around 20mm. Now is a good time to control any build up of moss and thatch allowing more air and water to reach the roots for a healthier, lusher lawn. A scarifying rake has tines to slice into the turf to remove dead plant material and cut through roots to stimulate new growth Think of it as vertical pruning - as essential as mowing - and should be done at least annually really.

Here's a great job to start the month! Any shrubs growing in pots will benefit hugely from top-dressing. Scrape away 2-3cm of the old compost from the top and replenish with new compost mixed with slow release fertiliser. I use Biochar N-P-K 5-5-5 organic pelleted, it's made in the UK and approved by The Soil Association. Perfect as the shrubs start to grow, this will also provide enough food over the spring and summer

The end of February is a great time to start emptying out your compost bins. In addition to saving you money, making and using your own compost as a spring-time mulch will improve the structure and health of your soil, increasing both the organic content and its water retention. Just take care when emptying as there may be toads, slowworms, mice and even hedgehogs living in the cosy environment of your compost bin!

This is the time of year I like to give soil in beds and borders a top dressing of an organic-based fertiliser. Blood, fish and bone, seaweed meal or pelleted chicken manure will all release nutrients slowly over two or three weeks as they break down in the soil, encouraging plants to grow steadily and sturdily. I think they avoid the rapid boost of soft growth susceptible to attack from pests and diseases which many synthetic/chemical fertilisers produce

It's time to prune some climbing plants! February is the most important month for wisteria - now is the time to cut back the stems shortened last summer to two or three buds which will promote the formation of flower-baring spurs. Type 3 clematis (such as viticella, jackmanii, 'Ville de Lyon', 'Arabella') will now be showing signs of growth and all stems can be cut back to around 30cm above the ground. These produce flowers on the new seasons growth and you want to be able to enjoy them at a sensible height

When temperatures are forecast to drop well below freezing anticipate problems by checking your containers. Any pots without plants are better off emptied before soggy compost freezes and expands. This is likely to cause far more damage than sitting empty. Ensure your protection for any vulnerable plants is still in place - mulches and fleece are particularly prone to being blown about by the wind

Getting some maintenance jobs done is a great way to get yourself organised for the new year - sharpen your lawnmower blade or book it in for a service, clean all your pots and seed trays ready to start sowing in a few more weeks and file a nice sharp edge on all your hoes because the weeds are already germinating!

If you're keen to do something in the garden after Christmas and it's not raining(!) why not take some hardwood cuttings, it's not too late. This could be particularly useful for hedging plants, because if you’re happy to wait out the time needed for new plants to establish and develop you could grow a new hedge completely for free by taking hardwood cuttings and heeling them into a slit trench in situ

Now is a great time to cut back the raggedy looking leaves on Helleborus x hybridus (also known as Helleborus orientalis). Doing this will ensure the new flowers and leaves emerging early in the new year will be shown off at the best. It'll also help protect the new season's growth from the fungal disease Hellebore leaf spot which you may see as round brown patches on the leaves. A generous mulch around the plants will also help.

Check deciduous shrubs for the 3 Ds – dead, diseased and damaged wood – all of which can be pruned out now plants are dormant. Focus your winter pruning on health and to shape. Non diseased prunings snipped up well are perfect as “browns” to be added to your compost

Continue to stay on top of fallen leaves by collecting on a regular basis to make leaf mould. Keep leaves off the lawn regularly but leave them on borders as a helpful mulch over winter

Now is the best time to plant tulip bulbs in pots and borders - make sure there is good drainage to prevent the bulbs from rotting

Start taking hardwood cuttings which is one of the most reliable ways of propagating deciduous trees, shrubs and roses. Pot them up or grow them in the ground. Be patient as they will take up to a year to develop roots - but you'll have many new healthy plants for free!

As climbing and rambling roses finish flowering, prune and tie in stems securely. This will help to prevent any breakages in windy autumnal weather

Before lifting main crop potatoes, it's important to cut off the foliage at ground level three weeks before. Blight spores can infect the tubers as you lift them, so this will prevent that and importantly will help to firm the skins of the potatoes too

September can often be sunny and warm so it's important to keep feeding and watering French and runner beans to keep them producing. You'll be surprised how many more you'll harvest if you continue picking them little and often to prevent them setting seed

In early September it's important to keep deadheading all your annuals and perennials to extend their flowering into the autumn. It's a good idea to continue feeding annuals in containers too