10 GARDENING MISTAKES – AND HOW TO AVOID THEM


by Liz Potter |
Updated on

Gardening is all about trial and error, but to save time, money and heartache, here are 10 common errors that are easy to avoid.

PLANTING TOO CLOSE TOGETHER

We’ve all done it – been seduced by the voluptuous planting schemes in RHS Chelsea show gardens, where plants are crammed in at about 30 per square metre for instant impact.

In reality, in our own gardens, it should be no more than four to six ‘groundcover’ plants, depending on their eventual height and spread.

When shopping, it’s a good idea to make a mental note of the plant’s eventual size before you buy. This way you can make sure you can give it the exact space it needs to grow. As a result, you’ll avoid having to hard prune it or move it in future. It also means your plants won’t sprawl ungainly over their neighbours.

NOT PRUNING VIGOROUS SHRUBS

Rampant giants such as buddleia, rambling roses and Clematis montana are famous for their vigour. For instance, Buddleia davidii can grow 2m (6½ft) in a season and then self-sow everywhere, if you don’t deadhead it. In small gardens either stick to slow-growing trees and shrubs, or invest in a good ladder and step up your annual pruning duties.

WRONG PLANT, WRONG PLACE

It was the late Beth Chatto who came up with the adage ‘right plant, right place’: a mantra for gardeners everywhere. The fact is, if you plant a shade-loving plant such as a hosta or hydrangea in a bright sunny spot, its lush green leaves will soon turn a crisp yellow and fall off. It’s far safer to partner sun-loving Mediterranean plants with a suntrap, and lush woodlanders with a shady glade.

OVERWATERING HOUSEPLANTS

The main cause of death for houseplants is overwatering: a form of ‘killing with kindness’. Decorative houseplant pots seldom offer any drainage, so plants are often left to sit in water and rot. When watering, poke your finger into their compost first to see how dry they are. Or, lift their inner pot to see if they’re sitting in a reservoir of water. If so, tip away the excess and let them dry out for a day or so.

NEGLECTING CONTAINER PLANTS

While it’s all too easy to overwater houseplants, we tend to under water our outdoor container plants. This is because, even if we have a lot of rain, our potted patio plants might be sat in a ‘rain shadow’ – sheltered by a porch, guttering or large shrub. Container plants depend on us for all their watering needs (and water-soluble nutrients), so keep an eye on compost moisture and douse them regularly in dry spells.

HARD PRUNING DELICATE SHRUBS

Some shrubs respond well to a good pruning, others can be hacked to death. The secret is to understand the difference between these two types of plants. Speed of growth is a good indicator of how well a plant will respond to pruning, and most can be pruned either while dormant or straight after flowering, depending on when they bloom and whether they flower on new or old stems. If in doubt, only prune shrubs that are really outgrowing their space, and then, only cut back by one-third straight after flowering, and see what happens.

DIGGING TOO MUCH IN WINTER

It’s one thing forking over the veg garden in autumn to clear away perennial weeds, but quite another to start digging it over and raking to a fine tilth ready for spring. Frost will do the hard work of breaking up any large lumps of clay, so there’s no need to chop up the soil and rake too early.

By overdigging before winter set in, you can unwittingly create a cap on the soil that’s pummelled and compacted into a hard crust by winter rain. No-dig champion Charles Dowding says it’s better for soil structure and friendly mycorrhiza if you simply dump a load of compost on top each spring. Job done!

NOT ADDING ORGANIC MATTER

Most of us complain our soil is awful, save for a lucky few who live in fenland or fine silty river valleys. But alas, it’s no good just ignoring it.

No plant can flourish in a compacted, heavy clay that bakes to concrete in summer, or a gravelly sandpit that’s dry as a bone all year. Adding well-rotted organic matter in spring will work wonders. Digging in leafmould, year-old horse muck and/or compost improves soil structure, nutrient levels and drainage, and helps sandy soils hang onto moisture and nutrients. Your plants will love it!

PLANTING LEYLANDII

This impressive conifer grows at a frankly shocking rate of 75-90cm (2-3ft) per year, even in poor soils. The tallest on record is 39m (130ft) – that’s taller than the Tower of London! Source of many a neighbourly dispute, leylandii is still very popular and often used as a giant hedge or shelterbelt in remote, windswept farmland. For residential urban areas, opt for a more attractive, slow-growing option that won’t suck all the moisture out of the soil and block all the light. Alternatives include beech (Fagus sylvatica), a line of pleached hornbeam (Carpinus betulus) or wildlife-friendly hawthorn (Crataegus monogyna).

LAYING TARMAC INSTEAD OF GRAVEL

Most families have at least two vehicles on their drive nowadays, so it’s all too tempting to turn your front garden into a plant-free forecourt that you don’t have to mow. However, this creates a problem of rainwater run-off and increases the risk of localised flooding after heavy storms. Gravel is a better option because this lets water soak away into the soil. Plus you can plant into it and, where there are plants, there’s potential for wildlife.

10 GARDENING MISTAKES – AND HOW TO AVOID THEM

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