Start here
Three ways in
Everything on this site keys off one number, your USDA hardiness zone. Set it once on this page and the plant lists, the pruning calendar, and the frost dates all adjust. Then pick the door that matches your problem.
I need plant ideas
Describe the spot (sun, wet or dry, deer, how much work you will do) and the plant finder builds a layered scheme you can push back on: more native, less work, taller, earlier.
Something looks sick
Start from the symptom, not the plant name. The plant doctor walks from what you see (yellow leaves, holes, wilting, dieback) to the likely causes, what to check, and what to do first.
I am holding pruners
The pruning pages tell you whether this month is the right month for this plant, and show the cuts: where on the branch, how much, and what never to do.
There is also a photo kit for getting a whole yard analyzed from pictures (what to shoot, what to write down, and the exact request to make), a month-by-month calendar, and a library of about 300 plants you can search by anything.
Your zone
Set it once
Type a US ZIP code and the 2023 USDA map answers. Or pick a zone by hand.
Zone is the coldest winter your yard usually sees, in 5-degree bands. It decides what survives, not what thrives; sun, soil, and water do the rest. Frost dates shown are typical, not guaranteed; a valley or a hilltop can run two weeks either way.
What this is, and what it is not
Groundwork is a reference for temperate gardens, written with the northeastern United States in front of it (zones 4 to 8) and general rules stated where they hold everywhere. It covers trees, shrubs, perennials, grasses, vines, bulbs, annuals, and the common edibles. It does not cover lawns, houseplants, or the tropics.
Care and timing advice was drafted from university extension services and botanical gardens, listed on the sources page, and then edited into plain language. It is a starting point, and a good one, but your county extension office knows your soil and your pests better than any website. Where a fact could not be confirmed against a source it is marked as such rather than stated with false confidence.
Plant identifications from photographs are always guesses until someone standing in the garden confirms them. The photo kit is built around that rule.
Plant finder
Describe the spot. Argue with the answer.
Pick the situation that matches your space and the finder assembles a planting scheme in layers, chosen from the library for your zone, with its reasoning showing. Then push back with the buttons: the scheme rebuilds around what you asked for. It is a way to think, and to see plants you would not have searched for by name.
The situation
Or filter the whole library
Every plant in the library, filtered by what you actually know about the spot. Bloom month finds plants for a gap; height keeps the front of a bed from swallowing the back.
Plant library
About 300 plants, with the parts people get wrong
Each card carries the facts that decide whether a plant lives (zone, sun, water), the facts that decide whether you like it in five years (mature size, deer, pests), and the one warning that matters. Search by common name, Latin name, or any word in the notes: try salt, wet, toxic, or hummingbird.
Deer ratings use the Rutgers scale (A rarely damaged, B seldom severely, C occasionally severely, D frequently severely) and match the Rutgers list for every plant it covers at species or genus level, checked entry by entry on September 25, 2026; the 47 genera Rutgers does not cover carry letters inferred from extension notes. Hungry deer in a hard winter eat plants they usually skip.
Pruning
When to cut what, and where the cut goes
Two rules cover most of the yard. Anything that flowers before the end of June carries its buds through winter on last year's wood, so prune it in the few weeks after it blooms. Anything that flowers after June blooms on wood it grows the same season, so prune it in late winter before growth starts. Dead, broken, and diseased wood can come off any day of the year. Nothing gets pruned after mid-August in the Northeast; the regrowth will not harden before frost.
Before you cut it
Pick the plant, or the kind of plant, and the month. The answer tells you whether this is the window, the edge of it, or the wrong time, and what to do instead.
The year, by pruning group
Green is the window. Pale green is acceptable with a caveat. The striped cells are the months when cutting costs you flowers, health, or hardiness. The gold outline is this month. Zones 4 and 5 run a week or two later in spring; zones 7 and 8 a week or two earlier.
Each group, in detail
The cuts themselves
Thinning cuts and heading cuts
A thinning cut removes a branch where it starts, at the trunk collar or at a side branch at least a third its size. It opens the plant, keeps the natural shape, and does not trigger a burst of regrowth. A heading cut shortens a branch to a bud or to nowhere in particular; it triggers a cluster of shoots below the cut. Thinning is the default for trees and most shrubs. Heading is for hedges, for pinching, and for rejuvenating shrubs that are meant to resprout.
How much in a year
About a quarter of a tree's live canopy at the outside, and less on an old tree; a third of a healthy shrub. Heavy corrective work gets spread over two or three years. One big limb off a mature tree can leave a wound that never closes.
Renewing an overgrown shrub
Two ways. The gentle one: cut a third of the oldest, thickest stems to the ground each year for three years, taking the others as new ones come up. The drastic one: cut the whole shrub to 6 to 12 inches in late winter; forsythia, lilac, privet, spirea, red-twig dogwood, ninebark, summersweet, and many others come back from that, and flower again in two years. Broadleaf evergreens mostly tolerate it (rhododendron, yew, holly, boxwood); needled evergreens except yew do not.
Never top a tree
Cutting the main limbs back to stubs starves the tree, opens every stub to decay, and produces a broom of weak shoots that break in the next storm. A topped tree is a removal on a delay. If a tree is too big for its spot, a crown reduction by an arborist cuts back to well-placed side limbs; if that will not do it, the tree is in the wrong place.
Wound dressings
Do not paint cuts. Dressings trap moisture, slow the woundwood, and stop nothing. The one exception is an oak or elm wounded between April and July, when the beetles that carry oak wilt and Dutch elm disease are flying; paint that cut within minutes with latex paint or a wound dressing.
Clean tools
Between plants, always; between every cut when removing diseased wood. Seventy percent isopropyl alcohol wiped on the blade works for most jobs. For fire blight, cankers, and black knot use one part household bleach to nine parts water, then rinse and oil the blade after, since bleach pits steel. Prune healthy plants first and the sick ones last.
Fire blight strikes
On apple, pear, crabapple, hawthorn, quince, and serviceberry: shoots that blacken from the tip and hook over like a shepherd's crook. In the growing season, cut 12 inches below the visible damage into clean wood, in dry weather, sanitizing between every cut, and burn or bag the prunings. Cankers seen in the dormant season are cut 6 to 12 inches below their lower edge. Never prune these trees during bloom or in warm humid weather when infection pressure is highest.
Hydrangeas, settled
Most hydrangea failures are pruning failures, and most of those come from not knowing which kind is in the ground. Match the flower to the row.
| What the flowers look like | What it is | Buds form on | Prune | Never |
|---|---|---|---|---|
| Blue or pink mopheads or lacecaps, June on; big glossy leaves | Bigleaf (H. macrophylla) | Last year's stems (rebloomers also on new) | Deadhead right after bloom; remove winter-killed stems in late spring once buds show | Cut live stems in fall, winter, or spring |
| Smaller blue or pink lacecaps; narrower leaves | Mountain (H. serrata) | Last year's stems | Same as bigleaf | Same as bigleaf |
| White cones in June turning pink; oak-shaped leaves; peeling bark | Oakleaf (H. quercifolia) | Last year's stems | Right after bloom, and only what you must | Winter or spring cuts |
| White cones in July aging pink; stiff stems; takes full sun | Panicle (H. paniculata) | This year's growth | Late winter, by a third or to a framework | Summer pruning |
| Round white heads in June on floppy stems | Smooth (H. arborescens) | This year's growth | Late winter, to 6 to 12 inches | Summer pruning |
| White lacecaps on a vine with peeling bark | Climbing (H. anomala petiolaris) | Old wood | Damaged wood only, after bloom | Hard cuts |
When to hire an arborist
Anything that needs a chainsaw off the ground, a ladder against the tree, or a limb you cannot control the fall of. Anything within 10 feet of a power line is not a job for you or for a general landscaper; branches touching lines belong to the utility, which will send a crew if you call. Hand tools from the ground, limbs under an inch with loppers and up to an inch and a half with a hand saw, are the homeowner's range.
Look for an ISA Certified Arborist, which means a passed exam and continuing education, and ask for proof of liability insurance. Walk away from anyone who knocks on the door saying your trees need work today, and from anyone who proposes topping. The ISA's free directory is at treesaregood.org/findanarborist.
Plant doctor
Start from what you see, not from the name
Most sick plants are not diseased. They are too deep, too wet, too dry, in the wrong light, or recovering from something that happened two summers ago. This page walks from the symptom to the likely causes in order of probability, tells you what to check before you treat, and says plainly when a thing is cosmetic and can be ignored.
Where is the problem?
How to look at a sick plant
The causes that are not diseases
Most of what kills a landscape plant is on this list. None of it can be sprayed for, and all of it can be fixed or prevented with a shovel, a hose, and a rake.
| Cause | How it looks | How to confirm | What to do |
|---|---|---|---|
| Overwatering, poor drainage | Leaves yellow and drop; summer scorch; sparse branching; roots brown and limp | Dig a hole and time the drainage; roots should be crisp with white tips | Stop scheduled watering; water only when the top 2 in are dry; raise the bed. Recovery takes years |
| Too little water in year one | Wilting that recovers after a soak; small leaves; scorch | Trowel into the root ball, not beside it | An inch a week (two on sand) through the first two falls; mulch |
| Planted too deep | Trunk enters soil like a post; slow decline; bark death at the soil line; girdling roots | Dig to the first structural root | Excavate to the flare; replant a young tree; air spade by an arborist on an old one |
| Mulch volcano | Off-color small leaves; dieback; rotting bark; rodent chewing | Pull the mulch back and look at the bark | 2 to 3 in deep, 3 to 5 in from a young stem, 8 to 12 in from a mature trunk |
| Girdling roots | Flat or sunken trunk face; early fall color; thin crown; Norway maple most often | Excavate the collar | Cut them at planting; on an old tree, an arborist judges whether removal is safe |
| Transplant shock | Small leaves, little growth, early color in year one | Check watering reaches the ball; flare at grade | Water; no fertilizer; prune only dead wood; expect a year of recovery per inch of trunk |
| Drought, a year later | Scorch, dieback, borers and cankers the season after a dry summer | Match the timeline to last year's rain | Deep water every 10 to 14 days in dry spells; mulch; no fertilizer or pruning while stressed |
| De-icing salt | Browning and dieback on the road side; late-winter evergreen burn; early fall color years later | Which side; distance to pavement; soil test for salts | Leach with heavy spring watering; burlap screens; calcium magnesium acetate instead of rock salt; do not pile salted snow on beds |
| Herbicide drift or weed-and-feed | Cupped, strapped, twisted leaves on many species at once; white new growth (glyphosate) | Timing after a spray; direction of wind; unrelated plants hit together | Water and wait; most recover. Photograph with dates; keep weed-and-feed off tree root zones |
| Contaminated compost or manure | Tomatoes, beans, peas, potatoes with cupped, thickened leaves in a newly amended bed | Pot test: seed beans in compost vs plain potting mix, compare in two weeks | Ask the seller where the feedstock came from; keep it off vegetable beds; the herbicides can persist over a year |
| Wrong light | Sun plants in shade stretch and stop blooming; shade plants in sun bleach and scorch | Count hours of direct sun in June | Move the plant, or change the plant |
| Reflected heat | Scorch on the side facing brick, pavement, a south or west wall | Which side browns; touch the wall at 3 pm | Water 10 to 12 in deep; mulch; heat-tolerant plants for that bed |
| Construction damage | Upper-crown dieback, sparse small leaves, one to three years after the work | Map where equipment, fill, and trenches went; protected zone is a foot of radius per inch of trunk | Water in dry spells; 3 to 4 in of mulch; arborist crown pruning; auger under roots next time instead of trenching |
| String trimmer and mower | Missing bark at the flare; early fall color; decay and borers enter; a full ring girdles the tree | Look at the flare on the mower side | A mulch ring or trunk guard so equipment never touches bark; no wound dressing |
When you need a lab, and where the labs are
A diagnostic lab answers in a week for about the price of a shrub, and it is the only way to confirm verticillium, bacterial leaf scorch, root rot pathogens, and most tree cankers. Send fresh material (a branch with the transition from live to dead, roots with soil for wilts, several leaves at different stages), wrapped in dry paper towel in a bag, with photos of the whole plant. Call first for anything unusual.
The year
What the garden wants this month
Written for zone 6, where the last frost lands in late April or early May and the first in mid-October. If you set your zone on the Start page, the frost dates below adjust and the note tells you how far to slide the timing.
The list
The two dates that organize everything
The last spring frost decides when the tender things go out: tomatoes, basil, annuals, dahlias, and the sunflower and corn seed. Plant a week after the typical date, or the day after a ten-day forecast shows nothing under 40 degrees at night. Cool-season plants (pansies, peas, lettuce, spinach, chard, kale, most perennials, every tree and shrub) can go in six weeks before it.
The first fall frost decides the other end: when to bring in the houseplants and ferns (before it, at 50-degree nights), when to lift dahlias (after it blackens them), when annuals are done, and when to plant garlic and bulbs (around it). Trees and shrubs planted in September and October root all fall and usually outgrow the same plant put in the following May.
Your yard, from photos
How to get a whole garden analyzed from pictures
A set of photographs and a few facts are enough for a careful analyst (human or machine) to name most of what is growing, map the beds, write a care card for each plant, and lay out the next twelve months. The quality of the answer depends almost entirely on the quality of the ask. This page is the ask.
What to photograph
- The whole yard from each side, standing at the property line and shooting toward the house. Four to six wide shots.
- Each bed straight on, from about 10 feet, so the whole bed fits in the frame with the house or fence for scale.
- Every plant you cannot name: one photo of the whole plant, one close-up of a leaf (top and underside), and one of a flower, fruit, or bud if there is any.
- Trunks and bark of every tree and big shrub, at eye level, plus the base where it meets the soil.
- Anything that looks wrong: the sick leaf next to a healthy one, the dead branch, the hole, the spot, the mushroom.
- Plant tags, receipts, or the old planting plan, if any survive.
- The same bed at 9 in the morning and 3 in the afternoon. Shadows tell the analyst which beds get sun.
- The downspouts, the low spot that puddles, and the strip by the road that gets plowed salt.
What to write down
What a good analysis contains
Compare whatever you get back against this. If it is missing a piece, ask for it.
- An inventory of every plant seen, each with a confidence label: certain, probable, or guess, and what would settle the guess.
- A map of the beds with the plants placed in them, however rough.
- A care card per plant: light, water, when it blooms, whether to deadhead, when and how to cut back, what commonly goes wrong.
- A month-by-month plan for the next year built from those specific plants.
- A list of what looks sick or badly sited, with the likely cause and the first thing to check.
- Hazards flagged: anything toxic to the animals or children you mentioned, anything invasive, anything about to hit the house or the wires.
- A short list of what it could not tell from the photos and what photo would answer it.
The request, ready to paste
Copy this into whatever assistant you use, attach the photographs, fill in the bracketed facts, and send it. It asks for exactly the pieces above, in that order, with the confidence labels and the safety rules built in. If a person built this site for you, send them the photos and the facts instead; this is the brief they will work from.
Reading your own photos
Before sending anything, three things you can read yourself. Shadow length and direction at 9 and 3 tell you which beds are really in sun; most "full sun" beds against a house get five hours. A dark, damp band at the bottom of a wall or a fence is the wet spot, and the plants there should be chosen for it. And a mulch cone piled up a trunk, or a trunk that goes straight into the ground like a telephone pole with no flare, is the single most common cause of a slowly dying tree; it is on the plant doctor page under abiotic causes.
Basics
The ten things that decide whether a plant lives
Most plants that die in their first two years die of one of these, and none of them is a disease. They are planting depth, water, mulch, and site. Fix these and the pruning and pest pages become a lot less urgent.
- Find the root flare before you dig. Pull potting mix off the top of the root ball until you see where the trunk widens into roots. That flare sits at or slightly above the finished soil level. Nursery pots and burlap balls are routinely 2 to 4 inches too deep, and a buried flare rots bark and starves the tree over five to ten years.
- Dig wide, not deep. Two to three times the width of the root ball, no deeper than the ball itself, so the plant sits on undisturbed soil and does not sink. Rough up the sides of a slick clay hole.
- Cut circling roots. Container roots that wrap the pot keep wrapping in the ground and strangle the trunk a decade later. Slice through them vertically in three or four places, or shave the outer inch off the ball. Remove all wire, twine, and burlap from the top third of a balled tree.
- Backfill with the soil that came out. Not compost, not bagged garden soil. Amended holes become bathtubs in clay and cause roots to stay inside the soft pocket. Save the compost for the surface.
- Water it in, then keep watering for a year. A new tree wants about 10 gallons per inch of trunk diameter each week in the growing season, slowly, at the root ball, when rain does not supply it. Perennials and shrubs want a deep soak (an inch of water) once a week rather than a sprinkle every day. Year two, taper; year three, it is on its own except in drought.
- Mulch flat, 2 to 3 inches, and pull it back from the trunk. A mulch volcano piled against bark holds water against it, invites rot and rodents, and makes roots grow up into the mulch where they dry out. The mulch ring should look like a doughnut, not a cone.
- Do not fertilize a new plant. Roots come first. Fertilizer pushes leaf growth the roots cannot support and can burn fresh roots. A soil test from your state extension lab (about $20) tells you if anything is missing; most established landscapes need nothing.
- Stake only if it will not stand. A trunk that moves in the wind builds taper and strength. If you must stake, use two stakes, a loose flexible tie, and remove them after one growing season. Ties left on girdle trunks.
- Plant for the size on the tag, not the size in the pot. An arborvitae planted 2 feet from the siding is a removal in ten years. Read the mature width, halve it, and that is the distance from the wall, the walk, and the next plant.
- Match the plant to the light and water you actually have. A shade plant in afternoon sun scorches; a sun plant in shade stretches and never flowers; a dry-land plant in the wet corner rots. The library filters exist for this reason.
Design, in five rules
Layers. A bed reads well when it has a back (shrubs or a small tree), a middle (2 to 4 foot perennials and small shrubs), and a front (under 18 inches, including groundcover). The finder builds in these layers because the eye expects them.
Repetition. Repeat the same plant in groups of three, five, or seven, and repeat one or two plants along the whole length of a bed. Twelve different plants in a row reads as a nursery; four plants, repeated, reads as a garden.
Succession. Plan for something in flower every month from March to October: bulbs and witch hazel early, the shrub flush in May, perennials in June and July, and the late shift (asters, goldenrod, sedum, grasses) that most yards forget. The library's bloom filter finds the gaps.
Structure. Roughly a third of the plants that show from the street should be evergreen or have winter shape (bark, seed heads, berries), or the yard disappears for five months.
Right plant, right place. The cheapest way to have a low-maintenance garden is to plant things that want the conditions you have, rather than amending the conditions to suit things you saw in a catalog.
| Common mistake | What happens | Do this instead |
|---|---|---|
| Arborvitae 2 ft from the house | Hits the eaves in 8 years; removed at 12 | Dwarf Hinoki, inkberry, or plant 5 ft out |
| Blue spruce in a suburban lawn | Loses lower branches to needle cast by year 15 | Concolor fir or Serbian spruce |
| Bigleaf hydrangea pruned in spring | No flowers that year | Deadhead only; or plant panicle hydrangea |
| Bradford pear anywhere | Splits in a storm and seeds the woods | Serviceberry or 'Winter King' hawthorn |
| Burning bush for fall color | Seeds into every woodland edge | Fothergilla, oakleaf hydrangea, blueberry |
| Hostas in deer country | Eaten to stubs by July | Ferns, hellebores, epimedium |
| Mulch piled on the trunk | Bark rot, root girdling, slow decline | Flat 2 to 3 in ring, pulled back |
| Sun perennials under a maple | Stretched, floppy, no flowers, thirsty | Dry-shade list: sedge, epimedium, wild ginger |
Plants to remove or never plant
These are still sold in some places and still standing in many yards. Each one seeds or runs into woodland and wetland where nothing eats it. The Massachusetts Prohibited Plant List (330 CMR 6.00; 151 species as of May 2026, checked September 25, 2026) bans sale, import, and propagation of most of them, cultivars included, with phase-out dates for recent additions; other northeastern states keep similar lists. Newly listed in Massachusetts in 2025 and 2026, and not in the table: black alder, jetbead, Japanese angelica tree, and sapphire berry.
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Common plants that are poisonous
Most garden plants are harmless, and most poisonings are a curious dog or toddler and one of the plants below. If something has been eaten, the ASPCA Animal Poison Control Center is 888-426-4435 (a fee applies) and Poison Control for people is 1-800-222-1222, both around the clock. The table follows the ASPCA plant pages, checked one by one on September 25, 2026, with Pet Poison Helpline and extension sources for the five plants ASPCA does not list; horses are left out unless the risk to them is unusual.
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Sources
Where this came from, and how far to trust it
The care, timing, and diagnostic content was drafted from the pages below (university extension services, botanical gardens, the International Society of Arboriculture, and trial gardens), read on September 25, 2026, then edited into plain language and reconciled where they disagreed. The plant library's horticultural facts (zones, sizes, bloom, native range) follow the Missouri Botanical Garden Plant Finder and Cornell and Morton references; deer ratings follow the Rutgers list where it covers the plant and are inferred from extension notes otherwise. Where sources conflicted, this site states the more conservative rule for zones 4 to 6 and says so on the page.
Reference databases
- Missouri Botanical Garden Plant Finder, the primary source for plant facts, plus its home-gardener problem pages on fungal leaf spots, powdery mildew, downy mildew, rusts, and black spot.
- Rutgers: Landscape Plants Rated by Deer Resistance (the A to D scale used here) and Rutgers FS1221, pruning flowering shrubs.
- Mt. Cuba Center trial garden reports (coneflower, phlox, monarda, asters, mountain mint, and sedge trials behind several recommendations).
- USDA Plant Hardiness Zone Map, 2023 edition; the ZIP lookup on this site uses a public mirror of that map.
- Frost dates by ZIP (Old Farmer's Almanac, NOAA-based).
- ASPCA toxic and non-toxic plant list, with Pet Poison Helpline for monkshood, bleeding heart, and bloodroot, Oregon State Extension for elderberry, and Ohio State for Kentucky coffeetree.
- Massachusetts Prohibited Plant List (the legal status column in the invasives table).
- Native Plant Trust and Xerces Society pollinator plant lists for native status and pollinator value.
Pruning
- Purdue HO-4, Pruning Ornamental Trees and Shrubs (the two-rule framework and the rejuvenation tables).
- University of Minnesota: Pruning trees and shrubs, oak wilt, fire blight, and disinfecting tools.
- UNH: Basics of pruning trees and shrubs and fire blight.
- Penn State: Pruning landscape trees, pruning ornamental plants, cutting down perennials in fall.
- UMass: Hydrangeas, pruning for blooms and University of Maryland: Pruning hydrangeas.
- ISA brochures: Pruning Young Trees, Pruning Mature Trees, Why Topping Hurts Trees; Find an Arborist.
- Morton Arboretum plant care pages on deciduous shrubs, evergreens, and trees.
- RHS clematis pruning groups and the Chelsea chop (method only; timing localized here).
- University of Maryland: Pruning roses; Iowa State on ornamental grasses; Oregon State on wisteria; Nebraska Extension on renewing lilacs.
Plant doctor
- Morton Arboretum plant care pages on chlorosis, leaf scorch, verticillium wilt, anthracnose, tree root problems, drought stress, winter injury, and choosing an arborist.
- UMass Extension fact sheets on tar spot, hemlock woolly adelgid, needle cast, protecting evergreens in winter, salt injury, and winter moth, plus the seasonal Landscape Message.
- Penn State: Diagnosing root death and Are my trees buried too deep; spruce spider mite.
- UConn: Nutrient deficiency symptoms.
- University of Minnesota on slugs, Japanese beetles, and cucumber beetles.
- Purdue: Emerald ash borer management; Michigan State on boxwood blight.
- Diagnostic labs: the URLs in the lab table were checked on September 25, 2026; fees are as published that day and change.
Planting and basics
- Morton: Caring for new transplants, how to water, construction damage.
- Rutgers FS099 on mulching; Purdue on tree wounds.
- Soil testing: UMass Soil and Plant Nutrient Testing Laboratory and the equivalent lab at each land-grant university.
Verification pass, September 25, 2026. After the site was built, a second pass checked 42 library entries against the Missouri Botanical Garden Plant Finder (no wrong native claims; six zone ranges and two bloom windows adjusted), every deer letter against the Rutgers list (90 letters brought into line with Rutgers; the library had run one letter more optimistic than Rutgers on most natives and conifers), the invasives table against the May 2026 Massachusetts list (Callery pear and maiden grass corrected to prohibited-with-phase-out), the toxicity table against the ASPCA pages (milkweed severity raised, cats added for Prunus, an unsourced yew quantity removed), and the frost windows against NOAA-based station dates (left as written). The full report is kept with the project files.
Built September 25, 2026. Corrections and additions are welcome; the site is a single file and easy to change.