Gardening Vocabulary Guide
New to gardening? Here are the terms you’ll hear at Goebbert’s and see in gardening articles. Quick, practical definitions for Illinois gardeners.
-A-
Aerate
Loosening up compacted soil so air and water can reach roots. You’ll see us recommend it for spots that feel hard as a brick after winter.
Amend Soil
Mixing compost or other organic matter into soil to improve texture and drainage. We talk about this constantly for Illinois clay soil.
Annual
A plant that lives one season – grows, blooms, sets seed, and dies all in one year. Petunias and marigolds are annuals. You replant them every spring.
-B-
Bare Root
Plants sold with no soil around the roots – usually dormant perennials or roses. They look dead but they’re just sleeping. Plant them as soon as the ground thaws.
Biennial
Takes two years to complete its life cycle. First year = leaves, second year = flowers and seeds, then it dies. Foxgloves are biennials.
Blossom End Rot
That dark, sunken patch on tomatoes or peppers. It’s a calcium problem caused by uneven watering, not a disease. Water consistently and mulch to prevent it.
Bolting
When lettuce or herbs suddenly shoot up a tall flower stalk. Usually means heat stressed them. Once they bolt, the leaves tast bitter.
-C-
Companion Planting
Growing plants together because they help each other – like marigolds repelling pests near tomatoes. It’s like having good neighbors in the garden.
Compost
Decomposed organic matter – kitchen scraps, leaves, and grass clippings broken down into dark, crumbly soil. Best amendment you can use.
Crown
Where a plant’s stems meet its roots – usually right at soil level. Plant too deep and the crown rots. Too shallow and roots dry out.
Cultivar
A specific variety that’s been bred for certain traits. Names in single quotes like ‘Autumn Joy’ sedum are cultivars.
Cutting
A piece snipped from a plant that you root to grow a new plant. Stick it in moist soil, keep it humid, and you’ll have roots in a few weeks.
-D-
Dead Spot
A stubborn patch where nothing grows. Could be compacted soil, buried debris, or a spot that stays too wet or too dry.
Deadhead
Snipping off spent blooms so the plant makes more flowers instead of seeds. Extends bloom time and keeps things tidy.
Deciduous
Trees and shrubs that drop their leaves in fall. Most Illinois trees are deciduous – maples, oaks, birches. Opposite of evergreen.
Deer Resistant
Plants deer usually avoid. Nothing’s deer-proof when they’re hungry, but astilbe, coral bells, and sedum rarely get touched.
Divide
Breaking one overgrown plant into several smaller pieces. Rejuvenates tired perennials and gives you free plants to spread around.
Drought Tolerant
Plants that survive with minimal watering once established. Sedum is the poster child – those thick leaves store water.
-E-
Evergreen
Plants that keep their leaves year-round. Pines, spruces, and boxwoods are evergreen.
-F-
Foliage
The leaves of a plant. When we say “grown for foliage,” we mean the leaves are more interesting than the flowers – like colorful coral bells.
Full Shade
Less than 3 hours of direct sun daily. North side of buildings or under dense trees. Astilbe and some coral bells can handle it.
Full Sun
Six or more hours of direct sunlight daily. Sedum, hardy hibiscus, and bee balm need full sun to bloom well.
-G-
Germinate
When a seed sprouts and starts growing. Different seeds need different conditions and take different amounts of time.
Ground Cover
Low-growing plants that spread to cover bare ground and suppress weeds. Creeping sedum makes great ground cover for hot, dry slopes.
-H-
Hardening Off
Gradually introducing indoor seedlings to outdoor conditions over 7-10 days. Start with an hour outside, then increase time daily. Skip this and your seedlings might die.
Hardiness Zone
USDA zones based on average minimum winter temps. Barrington is Zone 5 (-10°F to -20°F). If a plant says “hardy to Zone 5,” it survives our winters.
Heat Stress
When plants wilt or show crispy leaves during hot weather. Classic July problem. A deep morning watering usually helps them recover.
Heel In
Temporarily planting bare-root plants in soil to keep roots moist until you’re ready to plant them permanently.
-I-
-J-
-K-
-L-
Leaf Spot
Small brown or yellow spots on leaves from fungal infections. Common in humid Illinois summers. Usually not fatal, just ugly.
Leggy
Tall, spindly growth with lots of space between leaves. Usually means the plant’s stretching for more light.
Loam
Perfect soil – balanced mix of sand, silt, and clay. Drains well but holds moisture. Dark, crumbly, smells earthy. Most Illinois yards need compost added to get closer to this.
-M-
Mulch In
Spreading mulch around plants to keep moisture in and weeds down. Use 2-3 inches. Keep it pulled back from stems to prevent rot.
-N-
Native Plant
A plant that evolved naturally in a region. Bee balm is native to Illinois. Native plants are usually tougher and better for wildlife.
Node
The bump on a stem where leaves attach. Important for cuttings – roots usually form at nodes.
NPK
The big three nutrients – Nitrogen for leaves, Phosphorus for roots/flowers, Potassium for overall health. The numbers on fertilizer bags tell you how much of each.
-O-
Organic Matter
Decomposed plant and animal materials – compost, leaves, manure. Improves soil structure and feeds beneficial microbes. Illinois clay needs this added regularly.
Overwinter
Helping plants survive cold months – either outdoors with protection or indoors. Hardy perennials overwinter fine in the ground. Tender plants need to come inside.
-P-
Part Shade / Part Sun
Usually 3-6 hours of sun daily. For practical purposes, think morning sun with afternoon shade – that works for most part shade plants.
Perennial
A plant that lives more than two years, dying back in winter and returning from roots each spring. Sedum, coral bells, astilbe – all perennials.
pH Level
How acidic or alkaline your soil is (0-14 scale). Most plants prefer slightly acidic (6.0-6.8). Illinois soil tends to be slightly alkaline. Most perennials aren’t that picky.
Pinch Back
Nipping off the growing tips of stems so plants grow bushier instead of tall and leggy. Works great on herbs and mums.
Pinch Off Suckers
Removing extra stems that grow between tomato branches. These steal energy from fruit production. Snap them off when small.
Propagate
Starting new plants from existing ones through cuttings, division, or seeds. Sedum’s ridiculously easy – broken pieces root if they touch soil.
Prune
Cutting back branches or stems to shape plants or remove dead parts. Different plants need pruning at different times of year.
-Q-
-R-
Rhizome
A horizontal underground stem that spreads the plant. Iris and bee balm grow from rhizomes. You can divide them to control spread.
Root Bound
When roots circle tightly inside a pot because the plant outgrew its container. Always loosen root-bound roots before planting or they’ll keep circling.
-S-
Self-Seeding
When plants drop seeds that germinate on their own, giving you baby plants next year. Can be great (free plants!) or annoying (volunteers everywhere).
Soil Drainage
How quickly water moves through soil. Good drainage means no puddles and roots can breathe. Heavy Illinois clay drains slowly – add compost to improve it.
Stake
Supporting tall plants so they don’t flop in rain or wind. Tomatoes need staking. Put stakes in early before plants get big.
Succession Planting
Planting the same crop every few weeks so you get continuous harvest instead of one big glut. Works great with lettuce and beans.
-T-
Thin Out
Removing extra seedlings so the rest have room to grow. Feels brutal but makes a huge difference in final size and health.
Topdress
Spreading compost on top of beds without digging it in. It works down into soil with rain. Easy way to add nutrients without disturbing roots.
Transplant
Moving a plant from one spot to another – pot to ground, ground to pot, or one garden spot to another. Water well before and after.
-U-
-V-
Variegated
Leaves with more than one color – usually green with white, cream, or yellow markings. Adds bright spots to shade gardens even when nothing’s blooming.
-W-
Winter Heaving
When freeze-thaw cycles push plant crowns out of the ground. You’ll see it with coral bells. Just press them back into soil in spring.
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-Y-
-Z-
Questions about a gardening term?
Stop by Goebbert’s in Barrington and ask! Our staff loves helping new gardeners figure out the lingo. Whether it’s root-bound hostas, hardiness zones, or when to deadhead, we’re here to help.