Gardener’s Dictionary (Easy To Understand Defintions)

The gardening world is filled with all sorts of unusual terms and jargon and it’s confusing for anyone new to gardening. This dictionary for beginner gardeners will get you up to speed with all the popular and inside expressions.

This Beginner’s Guide to Understanding Plant Names is a good starting place too.

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Garden Dictionary

I remember when I was starting out as a gardener asking a gardening friend for advice and it was comical how many times I had to stop her to ask what some of the words meant.

Be sure to harden off the flat before sowing the borders!

Pardon?

I’ve jotted down a bunch of terms that come up fairly often when I chat with new gardeners. I am not (as you will soon see) a wordsmith of any sort, so forgive me if the definitions are a little choppy. I envy those who can write for the Oxford dictionary—it’s quite a talent. My aim is simply to help you understand these terms.

It’s also important to note that many garden terms are regional. I’m sharing the ones I notice. You may have a whole bunch more I’ve never encountered.

Getting Started

• Hardiness zone | A plant’s hardiness zone tells us where it can grow, withstanding the usual climate and seasonal temperatures. As a gardener, you want to know which zone you live in, and choose your plants accordingly. Most plants are suitable for a range of zones. I am in zone 6b, and many of my plants are suited to zones 4 to 8. The lower the zone number, the colder the climate. Zones 1-2 are up north (parts of the Yukon and Alaska). Zone 10 and warmer is in tropical areas of the United States.
  More: How to Find and Use Your Hardiness Zone here.
• Frost hardy | We say a plant is frost hardy when it goes dormant during the winter and resumes growth in spring. In other words, our coldest seasons do not kill it off.
• Tender plants | Plants that cannot withstand freezing temperatures.
• Native plants | One definition is native plants grow wild, locally, and have done so for centuries or more, prior to colonization.
  
  It can be complicated because it’s a non-scientific term and nature moves around.
  
  Living things including plants have shifted around the planet for millions of years and evolution is ongoing. Who decides the point in time that a plant is considered local or native? And, just like introduced species, native plants can be invasive or aggressive: it all depends on where they are growing. That said, the term generally means the plant has been growing in the region for hundreds of years or more, co-evolving with local wildlife.
  Introduced or alien species may or may not be invasive, may or may not provide food, nectar, or habitat to contribute to biodiversity.
• Pollinators | A name referring to a wide range of animals and insects that, by going about their business, inadvertently assist with the pollination (distribution of pollen) of plants, enabling sexual reproduction. Not all plants depend on pollinators, but many do.
• Soil | It’s very rare to have naturally wonderful garden soil. You will hear gardeners describe their soil in terms of sand, silt, or clay, or some combination of these, plus organic matter. Even within one garden soil quality can vary greatly. Loam is a combination of sand, silt, and clay.
  • The pH level of soil tells us how acidic or alkaline it is. A pH of 7.0 is neutral. Low numbers indicate acidity; higher than 7 indicates alkalinity.  Some plants prefer the pH a bit higher or lower than neutral. It’s always a good idea to run a few soil tests through a proper laboratory to have your soil analyzed. It’s informative for knowing if your soil could be improved with amendments, and, if so, which ones.
• Compost | It’s a noun and a verb. Here in Canada we use the word compost to mean the substance that forms when organic materials (food, leaves, cardboard) decompose. I notice on some garden shows (British and Australian) that it is also used to mean potting mix. I use my homemade compost to enrich my garden beds (see Composting 101: Fast & Slow Methods).
• If you are ordering garden soil or compost to be delivered to your house, it may come in yards. By this we mean cubic yards (3’x3’x3′) which is equal to 27 cubic feet. A yard of compost may weigh around 600 pounds (272 kg), depending on how moist it is. A yard of soil can weight as much as 2200 pounds (1000 kg). No wonder it takes me weeks to move several yards!
• Deadhead | When we deadhead plants, we remove the flower head that has finished blooming and is drying up often as seeds form. There are usually living leaves or a node at the junction right where you remove the old flower. Deadheading is different than pruning. Pruning is the removal of branches to improve the health or shape of a tree, vine, or shrub.
• Overwinter | When we overwinter plants, we provide conditions that help them survive over the winter. See How to Overwinter Plants for more.

Plants by Life Cycle

Annuals & Perennials: What’s The Difference? has more details.

• Annuals are plants that flower or fruit in the first year, including many flowers, herbs, and vegetables. Sunflowers are a good example of annuals. Annuals can be short-lived and just last for one growing season (spring and summer).
• Biennials have a two-year biological cycle. They grow leaves the first year, and flower, seed, and die in the second year. Foxgloves are biennial.
• Perennials are plants that live on for several years. They can flower or fruit year after year.
  • Herbaceous perennials are plants that die back down to the ground (or just have dead growth above ground) during the winter. The roots will send up new growth in spring.
  • Woody perennials like roses keep their woody stems year after year but their foliage drops at winter time.

Seeds

• Open-pollinated (OP) seeds are seeds that grow plants (“breed true”) just like their parent plants. Most heirloom plant seeds are open-pollinated.

• Hybrids occur when different varieties of the same plant species reproduce. This can happen naturally or with our help. The first generation of hybrid seeds are called F1 seeds, from the term filial 1, meaning “first children.” Seeds from plants grown from hybrid seeds will not grow true to type. Hybrids are not genetically-modified (GMOs).
• Heirlooms are open-pollinated, grow true to type, and passed along for generations.

• Genetically-modified seeds (GMO) have been artificially manipulated in a laboratory through genetic engineering. They may combine plant, animal, bacterial, and viral genes that would otherwise not naturally occur together. GMO seeds are only sold for agricultural use and not for home gardens.
• “Organic” on seed packets indicates the seed producer is legally certified as an organic grower.

See this simple beginner guide to types of seeds for home gardens for more information.

Seed Sowing & Propagation

• Direct sowing means sowing the seeds directly in the garden (in-ground or containers) where they will live out their happy plant lives.
• Indoor sowing means we start the seeds indoors. We may grow them until it is time to plant them in the garden, giving us a jump start over direct sowing, or continue growing indoors, if it suits the plant species.
• Winter sowing is method where we sow seeds in containers like plastic milk jugs and leave them in the garden during the cold months. This is used for seeds that require a stratification period (cold, damp chill period) in order to germinate.
• Days to maturity or Days to Harvest | The number of days it takes a plant—with the right conditions—to grow either from seed or a transplant (when it is established in the garden) to reach biological maturity. Check with your seed company to see which definition they are using. The same seed packet sold in different growing regions will list the same time estimate so it really is just that—an estimate—subject to all the usual variations like growing conditions, temperature, weather, climate, light, and so on.
• Damping-off is the name for a group of pathogens that fester in damp conditions and kill off seedlings. This can happen during indoor sowing. See tips for preventing damping-off.
• Harden(ing) off is the process where we prepare indoor seedlings and young plants for life outdoors.
• Potting mix | The stuff we use in flower pots and containers instead of garden soil. It’s soil-less, containing other lightweight, organic ingredients such as peat moss, perlite, vermiculite, sand, bark, or coconut coir. Some potting mix is organic and suitable for growing edibles. Watch out for non-organic mixes containing various additives (to help retain water) or fertilizers.
• Pricking out = thinning out seedlings. We do this when several seeds germinate close together and we need to remove some of the seedlings to allow the healthiest one(s) room and resources to grow.
• Cuttings and slips are the same thing: pieces of plants used for asexual propagation.
• Softwood cuttings | Late spring is the time for softwood cuttings from many plants, perennials, shrubs, and vines. These young cuttings are eager to root but also at high-risk for drying out without proper care. After softwood comes the greenwood phase. See How to Grow Plants from Softwood Cuttings.
• Semi-ripe cuttings | Summer is the time for semi-ripe cuttings when the base of the shoots are hardening up (maturing) but the tips are still nimble. The ripe  phase is next.
• Hardwood cuttings | By autumn, the plant growth is mature. Fall and winter hardwood cuttings can be slow to root but more stable than tender young cuttings, allowing over-wintering in a cool greenhouse or under some protection outdoors. See How to Grow Plants from Hardwood Cuttings.
• Other propagation methods include starting from seed, leaf-bud cuttings, tender cuttings, basal cuttings, leaf cuttings (vein, midrib, leaf slashing and squares), root cuttings, layering, division, offsets, and more.
• Fertilizer | Agents to promote soil health and plant growth. See this Guide to Organic Fertilizers for more info.
• Stratification | Chilling or prechilling, also called cold stratification, stratification, or cold treatment—along with applying moisture—is required for a number of cold hardy seeds. These are seeds that ripen in fall, stay dormant in the cold of winter, and sprout in spring when conditions are right.
• Scarification | If your seed packet instructions say to pre-treat your seeds before sowing by “nicking” or “sanding” the seed coat or soaking the seeds in water—these are scarification methods.

Hermaphroditic plants have male and female parts together within the same flower. A majority of flowering plants are hermaphroditic. Roses and lilies are examples. Some hermaphroditic plants are self-fertile (e.g. sour cherry, peach, and plum trees), while others still need pollen from other nearby varieties of the same species to produce fruit (blueberry, apple).

Dioecious plants house their male and female flowers on separate plants. Examples include holly, kiwi, and asparagus.

Monoecious plants can have male and female flowers in separate structures on the same plant. Examples include squash and cucumber.

Light Exposure Definitions

• Sunlight | see How to Assess Light Conditions in Your Garden for more information.

Plants

Related: How to Understand Plant Names | Botanical Latin

• Bare root plants | Some plants are purchased as ‘bare root plants’ meaning the soil has been washed off the roots and they are indeed bare. Some mail-order plants are shipped this way including asparagus crowns. This is done when the plant is dormant (not actively growing).
• Bulbs | Plants that grow from bulbs. Bulbs are fleshy plant bases that store food/energy for growth. These may be edible like onions, or ornamental like tulips.
• Climbers | Plants that grow vertically, often needing a wall or trellis for support. Roses can be climbers or shrubs.
• Cut flowers | Flowers grown specifically for cutting, used for bouquets or displays.
• Herbs are plants of which the leaves, stems, flowers, or roots can be used for food, flavour, scent, or medicinal purposes.
• Herbaceous plants by definition are flowering perennials that do not develop woody stems. Many herbs are herbaceous plants, but not all. Rosemary and lavender both develop woody stems, so, by this definition, they are not herbaceous but they are herbs.

Tools & Gear

These two innocent tools have started a lot of arguments! Many people think a spade is the one with the rounded tip. I can only guess that the confusion comes from spades in playing cards. But no, the spade is the one with the flat blade/cutting edge.

• Flats are trays of plants. In garden nurseries, you can often buy a whole bunch of potted plants together in a ‘flat’. There is also an expression in the gardening world for someone who is not quite with it. We say, he’s a plant short of a flat.
• Cold frame | A protective structure like a raised bed with transparent lid to retain warmth for plants and allow light in.
• Greenhouse | A structure with glass walls and roof for growing plants. A greenhouse may be heated by the sun or also have additional heat sources. I would love a nice, big one (10×20′) if you’d like to send me one. 🙂
• Lean-to Greenhouse | A greenhouse built against an existing structure. You can see my lean-to greenhouse here.
• Polytunnel | A greenhouse, hoop house, or similar structure covered in polythene (plastics), used for growing plants.

Misc.

• Biocontrols | Using beneficial (“good”) insects and microbes to control unwanted (“bad”) ones.
• Botanical name | There’s a lot of mayhem with plants names! We use the International Code for Nomenclature for plant botanical names. It’s our only hope for knowing if we’re actually talking about the same plants! Garden plants almost always have common names too. Problems follow when several plants share the same common name, sometimes also varying by region. Keep your sense of humor because the misunderstandings can get comical.
  More: How to Understand Botanical Names
• Beds or Garden Beds | Where we grow plants in the ground.
• Companion Planting | Much of it is folklore but there are science-based plant partnerships that can benefit our gardens.
• Raised beds | A box made from wood or other materials filled with soil for growing up off the ground.
• Borders | Garden beds (growing spaces), presumably around the sides of a yard or pathway.
• Guttation | This one isn’t used often: it’s just an interesting oddity. Ever see water seeping out of a plant’s leaves? That’s guttation. It can happen after watering, when the roots send water up through the plant and, you guessed it, out the leaves.
• Micro-climate | It’s a climate within a climate. We garden by geographical hardiness zones, but within any zone there may be hot or cool spots. Within my garden, a south-facing exterior brick wall provides a protected growing area a zone warmer than the rest of my garden.
• Microbial pesticides | Bacteria, viruses, and fungi (naturally-occurring) that attack bad bugs in soil.
• Nematodes | Microscopic worms in the soil. Can be beneficial, harmful, or neutral.
• Organic | Lots of uses for this word. In chemistry it means something that contains carbon and used to be alive. For some gardeners it can mean not using synthetic garden products including poisons, pesticides, herbicides, and so on.
• Pests are anything or anyone who annoys the gardener or interferes with plant growth and gardening.
• Prune | The act of removing parts of a plant to improve its structure or health or get rid of dead or diseased parts.
• Rust | Rusts are fungal diseases. One example is hollyhock rusts.

I hope this provides a good start. I know there’s plenty more. But at least now you can get a flat and harden it off before planting the border and know just what I mean.

~Melissa the Empress of Dirt ♛