How fast do common garden plants grow?

In the UK, growing season can often feel a bit short and unpredictable. It’s common to want to see results - and fast. So, how fast do common garden plants grow?

Unfortunately, there isn’t one simple answer. Salad leaves can be ready to pick in weeks, and trees can take several years to reach their mature size. Even the phrase ‘fast-growing’ can mean different things. 

It might describe germination, harvesting, or how much height a hedge gains each year. To clear up the confusion, Whitaker’s Garden Centre is breaking down which conditions can help (or hinder) the growth of popular garden plants. 

How plant growth rates are measured

When you’re a novice gardener, the labels on seed packets can sometimes feel like a new language. The most useful measurement for horticulturists depends on whether you’re growing from seed, waiting for flowers or crops, or choosing a plant to fill a specific space. 

1. Seed to germination

‘Time to germination’ measures how long it takes from the moment you sow a seed in moist soil until the first green shoot appears above the surface. 

Some seeds germinate in days; others need several weeks or particular temperatures and periods of cold before they will grow. Germination is the process of awaking a seed from its natural dormancy. 

2. Planting to flowering/harvesting

If you’re growing vegetables or cut flowers, this is often printed on packets as DTM (Days to Maturity). It measures the time from when the plant enters the active growing environment until it is ready to be picked or burst into bloom.

For example, the RHS classifies quick-growing vegetables as crops that can be ready in about 3 to 13 weeks after sowing or planting (exact timing varies by crop and conditions). 

3. Annual height and spread

Trees, shrubs and hedging plants are usually compared by how much height or width they gain each year. 

Annual height and spread tells you exactly how many centimetres (or metres!) of outward and upward growth a plant will put on in a single growing season. 

A Cherry Laurel might put on up to 60cm a year in height and spread, but a slow-growing Japanese Maple might only add 10cm - it’s relative to the plant species, and plant health can all affect the eventual height and spread. 

4. Time to maturity

Time to maturity is self-explanatory - it describes how long a plant is expected to take to reach its final adult size. This measurement is different from the time to its first flower or harvest. 

A perennial may flower during its first year but take several more years to develop into a larger, more established clump. In the same way, a young tree could provide blossom or fruit before reaching anything close to its eventual height. 

Common garden plant growth rates

Garden plants grow at very different speeds, and, as we’ve learnt, the first visible result isn’t always the same as full maturity. Selecting the right fast-growing varieties for your garden makes all the difference - but it’s good to remember that ‘fast’ is a relative term in gardening. 

A leafy vegetable might be ready to harvest within weeks, but a shrub still needs a season or two to establish its root system before it truly starts to grow. That’s why we’ve put together a quick-reference timeline for some of the most popular garden plants: 

What affects how quickly plants grow?

A plant’s growth rate isn't set in stone. 

In fact, specimens of the same variety can develop at different speeds depending on where and when they’re planted, the level of care they receive and the condition of their roots. If you want to hit the predicted timelines, giving your plants the right fuel is key:

1. Sunlight 

Plants convert sunlight into energy. Without enough of it, even fast-growing plants will become slow to establish. A sun-loving plant placed in a north-facing corner of your garden will grow at a fraction of its expected speed, so always check the plant label. 

Matching the right plant to the right light level is the biggest thing you can do for its growth rate. 

2. Soil quality/nutrition

Soil should provide roots with the right balance of nutrients, moisture and air. If you’re planting into compacted, nutrient-poor earth, your plants will struggle to push their roots out and access the food they need. 

3. Temperature 

Plants are very sensitive to temperature, both in the air and soil. 

Seeds won’t wake up and germinate if the ground is too cold, and the UK’s late-spring frosts are known for shocking young plants and stunting their growth for weeks. 

You can’t control the weather, but starting seeds indoors on a sunny windowsill or using a greenhouse can give your plants a warmer, earlier start to the season. 

4. Water/drainage

Moisture helps transport nutrients from the soil up through the plant's stems. A dehydrated plant immediately stops growing to conserve energy. 

But, given our rainy climate, the opposite is often the bigger threat: waterlogged soil suffocates roots, leading to rot. Always make sure that your garden beds aren't sitting in standing water, and your patio pots have sufficient drainage holes. 

Stock up on gardening supplies at Whitaker’s Gardening Centre! 

There may be no guaranteed shortcut to faster growth, but giving each plant the right conditions can make a massive difference. Start by choosing varieties suited to your garden’s light levels, soil and space, then support them with nutrients. 

Ready to get growing? Whitaker’s Garden Centre has everything - Explore our range of plants, seeds, compost, feeds, pots and gardening equipment online, or visit us in Merseyside for advice from our knowledgeable team. 

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