Gardening Terms Explained

Acclimatisation is when plants adjust to cooler (often outdoor) conditions. Often heard at the beginning of spring, before planting out plants that have been growing indoors over winter. Also see 'hardening off' which is the technique to help plants acclimatise for cooler conditions.

Acid soil is when the PH is lower than 7. Some plants, like nasturtiums or parsley, need acidic soil to thrive. Also see Alkaline soil.

Aerating is the practice of loosening compact soil, usually with a trusty garden fork to allow air in. This benefits your plants giving them good drainage and fertile ground to grow big and strong.

Alkaline soil is when the PH is higher than 7. Plants like lavender and forget-me-nots do really well in alkaline soil. Also see Acid soil.

A plant that will sprout, grow, flower, seed and complete its life cycle in a year. See also 'Perennial' and 'Biennial'.

Annual wildflowers grow, flower and set seed all in one year. Many self-seed freely, scattering new generations across the garden each season.

Bedding plants, including violas and sweet peas, provide immediate bursts of transient hues. They are ideal for garden beds, border landscapes, plant containers, and hanging baskets.

Bee-friendly flowers produce open, easily reached blooms full of nectar and pollen. They're crucial for supporting native bee species and healthy garden ecosystems.

Biennial is a plant that has a 2 year life cycle. Growing in the first year and flowering and going to seed before dying off in the second.

Blindness is when a bulb — daffodils most often — comes up with healthy leaves but produces no flower. The usual causes are overcrowding (the clump needs lifting and dividing), planting too shallow, cutting the foliage back before it has died down, or the ground drying out too soon after flowering so the bulb can’t build next year’s bud. Most cases are easily fixed once you know the cause.

Bokashi is a composting technique that comes from Japan, where the name means "fermented organic matter". It's different from usual composting in that it quickly breaks down food waste in a sealed container, using a special inoculant.

Bolting is when vegetables and herbs go to seed before you would like them to. Often brought on by stress — like a cold spell, lack of water or particularly hot conditions. It normally makes the vegetables and foliage woody, bitter to eat and virtually unusable. Very common with lettuce leaves and spinach.

Broadcast sowing involves scattering seeds across an area, rather than neatly planting them in trenches or straight rows.

In botany, a bud represents an immature or nascent shoot, typically found in the junction of a leaf or at a stem's end. A bud, once established, can either stay dormant for a certain period or start forming a shoot right away.

A bulb lasagne is a pot planted with several layers of different bulbs — the largest and latest at the bottom, the smallest and earliest near the top, each separated by a layer of compost. As each layer flowers in turn, a single container gives a long, changing display from late winter well into spring. See also ‘Container Growing’.

Butterfly-friendly plants attract adult butterflies with nectar-rich blooms and often provide larval foodplants for caterpillars too.

Chalky soil is pale, stony and full of calcium carbonate, which makes it alkaline. It drains freely and warms quickly in spring, but it rules out acid-loving plants like rhododendrons and camellias no matter how well you feed them. Choose plants that relish alkaline, free-draining ground instead. See also ‘Alkaline Soil’.

Yellowing plant leaves due to insufficient chlorophyll. Chlorosis can be caused by a number of issues, including disease, damaged or bound plant roots, highly alkaline soil, inadequate drainage, and/or nutrient deficiencies.

Clay is the heaviest of the soil types, made of very fine particles that pack tightly together. It’s sticky and mouldable when wet, bakes hard and cracks in summer, and holds water and nutrients so well it can be genuinely fertile — once you’ve opened up its drainage with organic matter. See also ‘Loam’ and ‘Sand’.

Coir is a natural fibre derived from the exterior husk of coconuts. It assists in maintaining soil moisture while simultaneously promoting drainage and aeration.

In gardening terms, a cold frame is like a mini greenhouse. It's a low-to-the-ground box with a clear top, designed to keep your plants safe from harsh weather. The clear top lets in the sunshine while keeping warmth from escaping, especially when it gets chilly at night.

Plants and vegetables grown near one another for mutual benefits such as attracting pollinators or deterring pests. Try growing chives near carrots to deter carrot fly, or sweet peas near broad beans to attract pollinators, or basil near tomatoes as they both love the same growing conditions.

Container growing means raising plants in pots, troughs, window boxes or hanging baskets rather than in open ground. It opens gardening up to patios, balconies and windowsills, and lets you give each plant exactly the compost and position it wants — but containers dry out fast and need more regular watering and feeding than beds. See also ‘Liquid Feed’.

When we talk about a plant's crown, we're referring to everything you can see above the ground — the stems, leaves, and any flowers or fruits. When a bunch of plant crowns grow together in one spot, we call it a plant community canopy.

Damp shade describes areas that stay cool, shaded and consistently moist — often at the bottom of slopes, near downpipes, or beside water butts. It's perfect for lush foliage plants like ferns and moisture-loving perennials.

Dappled shade is light that's filtered through leaves, fences or structures, creating a shifting pattern of sun and shade. Many woodland-style plants thrive in these conditions, enjoying gentle light without the scorch of full sun.

The time from when seeds are sown until the plant should be ready to harvest. A plant description or seed packet will usually outline the specific variety's expected growth timeline, though different care and growing conditions can lead to some variation.

Deadheading is removing a plant's spent flower heads, often as they start to seed. It can encourage new blooms. Usually, you remove the flower up to the node below it.

Deadheading is cutting off spent flowers to encourage the plant to bloom again, often flowering for a second time before the end of the season, extending the flowering period.

Deep shade describes areas that receive very little direct sunlight — such as under dense trees, behind walls or in narrow side returns. Only the most shade-tolerant plants will thrive here, so it's worth choosing carefully.

Direct sowing refers to planting seeds straight into the garden (whether in-ground or containers), where they will grow and thrive.

Dormancy is the resting phase a plant goes through, usually over autumn and winter, when growth slows right down or stops altogether. It’s a normal, healthy pause rather than a sign of trouble — the plant is conserving its energy and will pick up again in spring. Because a dormant plant can’t recover quickly from disturbance, it’s the wrong time to repot, feed or fuss.

Double flowers have been bred to carry extra rings of petals, giving that full, blowsy, many-layered look. The catch is that those petals are made by converting the flower’s pollen-bearing stamens, so there’s less pollen — and what nectar remains is often buried too deep for insects to reach. Lovely to us, frequently useless to pollinators. See also ‘Single Flowers’.

A drill is a straight, slim ditch dug in the ground where seeds are planted or young plants are placed.

A drought is a prolonged spell of dry weather when little or no rain falls and the soil steadily dries out. Established, deep-rooted plants usually ride one out — many wilt in the day only to recover by evening — while pots, seedlings and anything planted recently need the most help. Choosing drought-tolerant plants and mulching to lock in moisture are the long-term answers. See also ‘Mulch’.

Dry shade is found where tree roots, walls or overhangs keep soil both shaded and short on moisture. It can be one of the trickiest spots to plant, but certain perennials and groundcovers are well adapted to it.

Earth up refers to the practice of piling soil around the base of a plant. It helps to block light, safeguards against frost and stimulates root growth from the stem. It's a technique frequently used when cultivating potatoes.

Ericaceous plants are those that need acid soil to thrive — rhododendrons, azaleas, camellias, blueberries and the like. The word also describes the lime-free, acidic compost sold for growing them, which lets gardeners on chalky or neutral ground keep acid-lovers happy in pots. See also ‘Acid Soil’.

Espalier is a time-honoured gardening technique where you prune and tie branches of a woody plant, like a fruit tree, onto a frame. It's a way of controlling how the plant grows to boost fruit production.

An evergreen is a plant that maintains its foliage year-round. Evergreen species keep their leaves for over a year, continuously replacing older leaves over a gradual period.

F1 Hybrid is the first generation of plants produced by crossing two different purebred varieties. These hybrids are known for being vigorous and uniform. However, if you plant seeds from F1 Hybrids, they won't grow up to be the same as their parent plants.

Forcing is spurring growth when it's not the season — coaxing a plant to flower or fruit ahead of its normal schedule. It's mostly done in greenhouses or on a warm windowsill where you can manage light and temperature.

Frost-proof pots have been fired hotter and denser than ordinary ones, so they shrug off a British winter left outdoors — the clay simply doesn’t absorb enough water to crack when it freezes. If you want a pot to live outside all year, this is the label to pay for. See also ‘Frost-Resistant’.

Frost-resistant is a softer promise than frost-proof: the pot tolerates some cold, but may still flake or crack in a hard or prolonged winter. Fine for a sheltered spot or a mild year, but not a guarantee for a prized pot left out in the open. See also ‘Frost-Proof’.

FSC certified means a wood or paper product carries the mark of the Forest Stewardship Council, showing it came from a responsibly managed forest. When buying wooden tools, furniture, stakes or plant supports, the FSC logo is a reliable sign the timber was harvested with the woodland’s long-term health in mind.

A position in your garden that gets 6 hours or more of direct sunlight per day.

Germination is when a seed begins its physical changes, growing roots and leaves — the moment you've cracked its code to get it to grow.

The germination rate is the percentage of seeds expected to sprout under the right conditions.

Grafting is a technique where you join two plants together so they grow as one. The top part (the scion) is usually a branch or stem. The bottom part (the rootstock) is the one with the roots. The key is ensuring the vascular tissue of both plants connects well for the graft to take.

Grey water is the gently used water from your kitchen, bath, basin or washing machine — as opposed to fresh water from the tap. It’s perfectly good for watering the garden, as ordinary soaps and detergents won’t trouble your plants. Avoid anything from the toilet, and steer clear of bleach, disinfectant and dishwasher salt, which harm the soil over time.

Hardening off is the method of gradually acclimatising sprouts and plants grown indoors or in a greenhouse to outdoor temperatures. Without hardening off, your sprouts may get stressed, wilt or die off. See also 'Acclimatisation'.

Plants that are tough enough to survive winter without any protection. Ordinarily this means the plant is capable of withstanding outdoor winter temperatures down to -15°C.

A herbaceous plant is a type of perennial that doesn't develop woody stems or branches. These plants often retreat into dormancy during winter through their underground roots or woody base, returning to active growth in spring.

In the green describes buying and planting certain bulbs — snowdrops, bluebells and winter aconites — as growing plants still in leaf, just after they’ve flowered, rather than as dry autumn bulbs. These plants dry out easily and establish far more reliably this way, bought in bundles and settled straight into the ground in late winter.

A node is the area on a stem (often swollen) at which point a leaf, leaf bud or shoot will emerge. The internode is simply the area between two nodes. It is a term often referred to when propagation advice is given: a nodal cutting is taken directly below the node where there is most hormonal activity, while an internodal cutting is taken in the internode region.

Who is John Innes, and why does he have such a compost monopoly? Turns out he isn’t a brand, he was the 19th century founder of a horticultural research institute. The composts named after him are soil-based recipes formulated for propagating seeds (1), potting on seedlings (2) and mature plants (3), with fertiliser content increasing from 1-3.

The last frost date marks the final cold spell in spring where you live, so you know when it's safe to plant out tender plants. These dates differ based on your location — the region, altitude, and whether you're in the city or the countryside.

Leafmould is the dark, crumbly material left when autumn leaves are allowed to rot down on their own. Gather fallen leaves into a bin or wire cage, leave them a year or two, and they break down into a soft, soil-like matter that’s brilliant for sowing seeds, potting on, or improving the ground. It costs nothing but patience.

"Leggy" refers to seedlings that have grown too tall and thin, usually from reaching for light. These seedlings tend to be weaker and more likely to fall over. Avoid legginess by ensuring seedlings get plenty of bright light.

Liquid feed is a fast-acting plant food diluted in water and applied as you water, giving plants a quick hit of nutrients. It’s especially useful for containers and hanging baskets, where roots soon exhaust what the compost can offer — a weekly feed through the growing season keeps flowering plants going. See also ‘N-P-K’.

A fertile soil mixture made up of roughly equal amounts of sand, silt and a little less clay (about 40-40-20%). Loam is considered ideal for retaining nutrients well and absorbing water while still allowing excess water to drain away.

Meadow sowing is the process of scattering wildflower and grass seed over prepared ground to create a natural or semi-natural planting.

Micro greens are young, leafy vegetables and herbs harvested whilst they are still sprouts. With their small tender leaves, they often have a concentrated flavour and are rich in nutrients.

Mulch is material spread over the ground and around plants to keep the soil moist, suppress weeds, and improve the soil over time. You can use well-aged manure, compost, leaf mould or even gravel.

N-P-K stands for the three key plant nutrients: nitrogen (N), phosphorus (P), and potassium (K) — also called macronutrients. The three numbers on a fertiliser bag refer to the ratio of these nutrients.

Wildflowers that naturally occur in the UK landscape, supporting local ecosystems and pollinators.

Naturalising is letting bulbs and plants spread and settle as if they had arrived on their own, coming back and multiplying year after year with no help from you. Daffodils, crocus and snowdrops naturalise especially well in grass or under trees, so a modest first planting slowly becomes a generous drift. See also ‘Self-Seeding’.

Planting in a loose, informal way that mimics meadows and wild habitats.

Nectar-rich plants produce plenty of sweet nectar that fuels pollinators. They're the backbone of wildlife-friendly gardens.

No dig is a way of growing that leaves the soil undisturbed rather than turning it over each year. Instead of digging, you feed the soil from the top with a layer of compost and let the worms and fungi do the work below. The result is fewer weeds, better structure, more moisture held in the ground — and a good deal less effort.

A nursery pot is the plain plastic pot a plant is grown and sold in. It’s functional rather than pretty, with good drainage holes — many gardeners leave the plant in it and drop the whole thing inside a decorative outer pot, lifting it out to water. See also ‘Container Growing’.

Plant varieties that produce seeds that are 'true to type', growing into near identical plants to the parent. Unless stated as a hybrid, a plant is often open pollinated. Choosing open pollinated varieties supports seed biodiversity.

Organic matter is decayed plant and animal material — well-rotted manure, garden compost, leafmould or composted bark — laid over or worked into the soil. It’s the most useful thing you can add to any ground: it opens up heavy clay to improve drainage, and helps light, sandy soil hold onto moisture and nutrients. See also ‘Mulch’ and ‘Leafmould’.

Partial shade usually means a spot that gets around 3–6 hours of direct sun a day, often morning or late afternoon light. It's a sweet spot for many flowers, herbs and leafy plants that need protection from the strongest midday sun.

Peaty soil is dark, spongy and rich in partly decomposed plant material, holding a great deal of moisture and tending towards the acidic. It’s rare in gardens — and because peat bogs are precious, threatened habitats, gardeners are now encouraged to leave peat in the ground and choose peat-free composts. See also ‘Acid Soil’.

Peat-free compost is potting compost made without peat, using materials like composted bark, coir, wood fibre and green compost instead. Peat bogs are precious, slow-forming habitats and important carbon stores, so choosing peat-free keeps them in the ground where they belong. Modern peat-free mixes perform just as well for most plants. See also ‘Peat’.

Perennial means a plant that lives for more than 2 years. Also see 'Annual' and 'Biennial'.

A perennial wildflower is a species that returns year after year. It goes dormant over winter and regrows in spring, helping build a long-term, self-sustaining meadow.

Pinching out means removing the growing tips of a young plant to encourage it to sprout side shoots. It's a neat trick to make plants grow in a fuller, bushier way and produce more flowering stems.

Pollination is the process of moving pollen from one flower to another. It can happen with help from the wind, insects, animals, or by hand.

A connected pathway of pollinator-friendly plants that supports bees, butterflies, and other beneficial insects.

Plants described as pollinator-friendly offer abundant nectar and pollen for bees, butterflies, hoverflies and other beneficial insects.

Pot feet are small supports — ceramic, stone or plastic — that raise a container off the ground so water drains freely from the base rather than pooling underneath. They keep roots from sitting wet and, in winter, stop a pot standing in an icy puddle or freezing to the ground. A couple of bricks do the same job.

Pot on means taking a plant out of its current container (usually because it's grown too big for it) and moving it into a new, roomier one so it can keep growing.

Pot-bound (also called root-bound) describes a plant that has outgrown its container, its roots wound round and round in a dense mat with little compost left. Tell-tale signs are roots pushing through the drainage holes and a plant that dries out the moment you water it. It’s the clearest sign a plant genuinely needs potting on — though some flowering plants bloom all the better for being a little pot-bound. See also ‘Pot On’.

Pricking out is when you move seedlings from pots or trays to give them more space to grow, normally when their first set of true leaves have appeared.

Propagation is the act of producing new plants using a range of techniques, such as growing from seeds, using cuttings or grafts, or dividing existing plants.

Root rot is a fungal disease that affects the roots of plants, often causing them to wither and die. It is frequently caused by overwatering or plants in pots without adequate drainage.

The mix of roots and soil that comes with a plant when you remove it from its pot or lift it from the ground.

Sandy soil is made of large, gritty particles with plenty of space between them, so it drains fast and dries out quickly. It’s light and easy to dig, but hungry and thirsty, quick to lose both water and nutrients. Adding organic matter helps it hold onto more of both. See also ‘Loam’ and ‘Clay’.

Scarifying, also called de-thatching, clears accumulated dead grass (thatch) from your lawn. Getting rid of the thatch lets water and nutrients reach the soil and helps healthy grass thrive.

A seed mix combines several varieties in one packet for easy, blended planting — often seen in wildflower or salad mixes.

Seed packets include vital information such as sowing times, spacing, germination temperature and expected harvest dates.

Seed viability is a seed's ability to germinate successfully — influenced by age, storage conditions and seed type.

A plant in its early stages of life, grown from a seed.

Self-seeding plants scatter their own seed, allowing new seedlings to appear each season — a natural way for gardens to fill out with minimal effort.

Silt is a soil of medium-sized particles — finer than sand, coarser than clay — that feels smooth, almost soapy, when wet. It’s fertile and fairly good at holding moisture, but it compacts easily and can wash away on sloping ground. See also ‘Loam’.

Single flowers have just one ring of petals around an open centre, leaving the pollen and nectar easy for insects to reach. They may look plainer than their frilly double cousins, but they’re far more valuable to bees, butterflies and hoverflies. A good rule: if you can see the centre of the flower, so can a pollinator. See also ‘Double Flowers’.

Sowing depth is how deep a seed is planted — follow packet guidance, as tiny seeds often need light to germinate and should be sown on the surface.

Spacing is the distance you leave between seeds in a row, and between rows. Larger plants need more room than small ones — follow packet guidance to avoid competition for light and nutrients.

A spacing guide outlines the ideal distance between plants so they have room to grow without competing with one another.

Stratification simulates the natural cold and damp conditions a seed would experience over autumn and winter, breaking its dormancy. Seeds are placed in a moist, cold environment (often the fridge in a damp bag) before being brought out to sprout.

Succession sowing is a gardening strategy where you plant new seeds at regular intervals throughout the growing season, staggering harvest times for a steady, prolonged yield rather than a glut. It is particularly useful for fast-growing vegetables like radishes, beans, or salad greens.

Successional flowering describes plants blooming at different times so there's colour — and food for pollinators — from early spring through to late autumn.

Thinning out is removing surplus seedlings that have sprouted too close together, allowing the strongest ones to grow with less competition for light and nutrients.

Tilling means breaking up the soil to prepare it for planting. Effective tilling loosens soil to a depth of around 8–10 inches, creating an aerated bed for seeds or seedlings.

Tilth is the top layer of soil that has been broken down into small, loose pieces through digging and raking — the ideal fine, crumbly texture for sowing seeds.

Transplanting is the process of relocating a young plant, typically from a pot, to its final spot in the garden where it's set to flourish.

Vermiculite is a natural mineral heated to high temperatures, resulting in lightweight, super-absorbent flakes. Mixed into a growing medium, it boosts aeration and helps retain moisture and nutrients.

A water butt is a container — often a barrel — that collects rainwater from a roof via the drainpipe, storing it for use in the garden. Stand it up on bricks and you’ll have room for a watering can beneath the tap. It’s the simplest way to water your plants with rain rather than treated mains water.

Waterlogged soil or pots have an excess of water with nowhere to drain. Best avoided by using free-draining compost and, for pots, lifting containers off the ground in winter.

A weed is simply a plant that's ended up somewhere it's not wanted or supposed to be.

A wildflower meadow is a mix of native grasses and flowering plants grown together to create a natural, biodiverse habitat. Meadows are rich in pollen and nectar, supporting bees, butterflies and beneficial insects.

An area planted with wildflower seeds to attract pollinators and increase biodiversity.

A wildlife pond is a small body of still water added to a garden to support frogs, newts, insects and the creatures that feed on them. It needn’t be grand — even a sunken washing-up bowl or an old sink will do. Gently sloping sides, or a stone ramp, let animals climb in and out safely. Few things bring in more life, more quickly.