The most common gardening mistakes of 2024 and how to avoid making them again in 2025

Late sowing causes problems such as small harvests, small fruits and immature crops. Some crops, such as tomatoes, need a long growing season, and a late sowing can result in a lot of green tomatoes that haven't ripened before autumn.

If the weather is dull and cold consider investing in a heated propagator or mat to increase germination rates indoors. When sowing direct, keep an eye on weather forecasts. For crops like broccoli, which needs a long growing period, if it's a cold or wet spring, it may be worth sowing indoors into modules and transplanting seedlings when the weather improves.

If limited time is the issue, start small, growing only a few vegetables – either the ones you most like to eat or those that are most expensive to buy. January is a good time to plan ahead. Look up ideal sowing times for the veg or flowers you want to grow and mark sowing times on your calendar. Organising seed packets into sowing months can also act as a useful reminder.

Inadequate slug defences

If the spring or summer is particularly wet, slug populations can increase rapidly. Seedlings and young plants are at most risk from slug attacks as well as mature plants such as hostas which are often targeted by slugs. There are several ways to tackle slugs. Keeping on top of populations early will help but bear in mind that slugs also provide food for wildlife.

• Biological control – apply nematodes in the spring to reduce slug populations. Follow instructions carefully as nematodes need to be used when the soil reaches a warm enough temperature, at least 5ºC
• Traps – put a beer trap in your border near vulnerable plants. Make sure the top is 1cm above the soil surface to prevent other creatures falling in
• Encourage wildlife – putting a pond into your garden will encourage frogs and newts, which eat slugs. Encourage other wildlife such as birds and hedgehogs to keep slug populations down
• Copper rings – these are useful for protecting newly planted hostas and other popular slug targets, such as strawberries
• Handpicking – go round the garden with a torch and pick off any slugs. Move them to the compost heap, where there will be lots to feed on or a long way from your plants, as they will find their way back

Overwatering or under-watering

Overwatering plants like tomatoes can lead to problems such as blossom end rot, while too much water for plants that thrive in dry conditions, such as lavender and succulents, can lead to root rot. Stick your finger into a container to check that the top 3cm of compost is dry before watering. Drought tolerant plants should only need regular watering until established. For fruit and vegetables, keep an eye on the weather forecast to make sure you're not watering just before heavy rainfall.

Under-watering can also lead to plant problems – symptoms can include shrivelled leaves, a drooping plant and slow growth. Plants in containers will need more regular watering than those in the ground, even after rain, as the water may not get down to the plants' roots. For those in the ground, focus on watering new plants, aiming the water at the plant's roots rather than watering from above.

Not keeping on top of weeds and vigorous plants

The best way to keep on top of weeds is to tackle them early. Use a weedling ID chart and dig out early weeds as soon as they emerge in the spring. Tackle weeds little and often before plants start to put on growth and make it harder to spot weeds in your borders.

Pruning can help keep vigorous plants under control, as can dividing any large clumps of herbaceous perennials that have become overgrown. If you find you are continually pruning a shrub to keep it under control, it may be worth removing it and replacing it with something more manageable.

Buying too many plants and not planting them soon enough

It can be hard to resist buying a new plant at a flower show or garden centre, but if you don't have time to plant them it can be an expensive occupation. If you need new plants, but don't have time to plant them, heel them in (plant them temporarily) until you have time to plant them in their final position. If the problem is procrastination, because you're not sure where the plants should go, making a planting plan in January when there is less to do in the garden could help. Take pictures throughout the year to identify any gaps in your displays, then make a list of the plants you need, rather than buying on impulse. If the problem is time based, focus on keeping the plants healthy in their pots until you have time to plant them. Don't let them dry out, move them out of full sun and prioritise plants that are likely to deteriorate first.

Going on holiday at the wrong time

Coming back from holiday to find all your potted plants are dead is not the way to end a relaxing break. A holiday where you optimistically count on a bit of rain is bound to coincide with a heatwave. Aside from asking neighbours and friends to come in and water every few days there are other options.

Setting up an irrigation system with a timer can be an efficient way to ensure your plants survive your holiday. For veg such as greenhouse-grown tomatoes, there are gravity-fed watering systems with drippers, which can water up to six plants. Moving pots into the shade before you leave and grouping containers will help reduce evaporation – and make it easier for anyone who may be doing your watering for you.

Planting plants in the wrong place

Placing plants in the wrong place, such as too close together or in conditions they don't like is an easy mistake to make. It can be difficult to imagine that the small shrub you bought at the garden centre will ever spread to a metre wide, but not allowing enough space for plants will create a lot of future work if you have to transplant perennials and shrubs to new locations, and plants that grow too big for their space can shade out neighbouring plants. Check the height and spread before planting and check the plant will have enough room once mature.

Following the mantra, 'Right plant, Right place' may mean you can't grow all your favourite plants, but a plant that thrives in clay soil will always struggle in sandy soil and gardening will be easier, cheaper and more satisfying if you buy the right plants for your garden from the outset. Do a soil test for pH, check your soil's consistency and how much sun the planting area gets before buying anything.

Not protecting plants against birds and insects

The best way to protect plants from birds such as pigeons is to use netting or put up a fruit cage. Netting placed over hoops or bamboo canes to create a frame can prevent birds from eating ripening fruit or feeding on the leaves of brassicas. Use a fine mesh netting if you have a problem with insects such as caterpillars. This can prevent butterflies laying eggs on the leaves of brassicas. The alternative is to pick eggs and insects off by hand. Unless insect infestations are severely affecting plants, it's beneficial to your garden's ecosystem to tolerate some insect pests, as they provide food for birds. Creating a wildlife-friendly garden can help reduce pests.

Not being realistic about the amount of time you have

There are lots of ways to make gardening more low-maintenance. If you feel like you're continually behind, why not look at ways to cut down your gardening to-do list. Here's a few ideas:

• Save time on watering by buying drought tolerant plants
• Buy veg plug plants to save time on sowing and potting on
• Use ground cover plants to suppress weeds
• Grow fruit and veg that doesn't require much attention – courgette, beetroot, dwarf French beans, rhubarb and strawberries all provide tasty crops without the need for tying in, potting on or staking
• Include evergreen shrubs that will add structure but need no deadheading and little pruning, such as abelias

Pruning mistakes – not pruning enough or pruning at the wrong time

The most common results of pruning mistakes are overgrown shrubs, lack of flowers and excessive leafy growth. Check your plant's pruning needs before making any cuts. Some common mistakes include:

• No flowers – most flowering shrubs should be pruned after flowering to avoid this. The general rule is to prune shrubs and climbers that flower before June immediately after flowering, and those that bloom after June, in winter
• Overgrown shrubs – giving overgrown shrubs an all over trim encourages a mass of stems and few flowers. To rejuvenate an overgrown shrub, remove a third of the oldest stems each winter, then reduce the remaining stems by half after flowering