Field Guide · Reference
Salt Tolerance For seed & plantings
Salt reaches plantings in two main ways: road de-icing salt that splashes or runs off onto roadsides and medians, and seawater from tides, storm surge and wind-blown spray along the coast. Every species page lists a salinity tolerance rating so you can match plants to how much salt a site gets.
The ratings
High. Tolerates regular tidal or brackish inundation, or direct coastal salt spray. These are the species for lower marsh, dunes and back-dunes.
Moderate. Tolerates roadside salt spray and periodic brackish influence. Use them along roads that are salted in winter, in upper tidal marsh and in coastal buffer zones.
Low. Tolerates occasional or incidental exposure, such as infrequent de-icing runoff on inland sites, but not regular salt.
None. Freshwater only. Keep these species out of the road-salt splash zone and away from coastal spray.
Unknown means we don’t have reliable information for the species yet. Treat it as low until proven otherwise.
Matching species to the site
- Roadsides and medians: the first few feet from a salted road get the most spray and runoff, so use moderate or high species there and lower-tolerance species farther back.
- Parking lots and stormwater basins: basins that collect runoff from salted pavement concentrate salt, so favor moderate or high species in the bottom and inlets.
- Coastal sites: match tolerance to the zone, with high-tolerance species where tides and spray reach and moderate species in the buffer behind them.
Salt stress adds to drought stress, so plantings on salty sites benefit from careful watering while they establish.
Find salt-tolerant plantsBrowse our salt-tolerant collection, or check the Salinity Tolerance line in the specifications on any species page.
Here are the terms you’ll come across in our guides, on our seed labels, in our availability lists and on our species pages, for both seed and plants.
Balled and burlapped (B&B) describes a tree or shrub dug from the field with its root ball wrapped in burlap. We grow in containers and don’t sell B&B stock.
Bare root describes a dormant plant sold with no soil around its roots. We don’t sell bare-root stock.
Bulk weight is the total weight of seed material in the bag, including inert matter and non-viable seed. Compare it with Pure Live Seed.
Bulking agent is an inert carrier, such as sand, clay kitty litter, rice hulls, sawdust or vermiculite, that’s mixed with small seed so it spreads evenly.
Cell is one pocket of a flat. A flat’s cell count (for example, a 50-cell flat) is how many plants it holds.
Container sizes (#1, #2, #5, #7) are nursery trade sizes for potted plants, roughly 1, 2, 5 and 7 gallons. Larger containers mean larger, older plants. Pot dimensions and typical heights are listed in Plant Sizes & Spacing.
Cool-season grass is a grass that grows mainly in spring and fall and slows down in summer heat.
Cultipacker is a ridged roller used to firm a seedbed and press seed into the surface.
Deep plug is a plug grown in a deeper cell, 4″ deep × 2″ in diameter, for deep-rooted or taprooted wildflowers such as Butterflyweed and Common Milkweed. Sold by the flat of 50.
Dibble is a pointed hand tool for opening planting holes for plugs and tubelings.
Dormant seed is viable seed that won’t germinate until a requirement, such as a cold period or a softened seed coat, has been met.
Dormant (frost) seeding means sowing in winter, roughly December to March, so that freeze–thaw cycles work the seed into the soil.
Ecotype (local ecotype) describes a population of a species that is adapted to the climate and soils of a particular region. Most of our plants and seed come from seed we collect ourselves, so they are local-ecotype.
Flat is a tray of plugs or tubelings, about 11″ × 22″. We sell plugs and tubelings by the full flat.
Forb is a broadleaf, non-woody flowering plant, as opposed to a grass or grass-like plant.
Frost heave is when freezing and thawing soil pushes young plants, especially small plugs, up out of the ground. Mulch helps prevent it.
Germination rate is the share of seed that sprouts during a standard seed test.
Graminoid covers grasses and grass-like plants such as sedges and rushes.
Hemiparasite is a plant that photosynthesizes but also draws water and nutrients from the roots of a host plant.
Inert matter is the chaff, stems, soil and other non-seed material in a seed lot.
Inter-seeding means sowing native seed into existing desirable vegetation to increase its diversity.
No-till drill is a seed drill that cuts through residue and places seed without the soil being tilled first.
Nurse crop is a fast, short-lived grass sown with a native mix to give quick cover. See Cover & Nurse Crops.
On center (O.C.) is plant spacing measured from the center of one plant to the center of the next, as in “18 inches on center.”
Plug is a young plant grown in a small cell with an established root ball. Our plugs are grown in cells 2″ deep × 2″ in diameter and sold by the flat of 50, kept trimmed to about 6–8″.
Pure Live Seed (PLS) is the share of a seed lot that is pure, viable seed of the labeled species, calculated as purity × total viability. See PLS & Seeding Rates.
Purity is the share of a seed lot, by weight, that is seed of the labeled species.
Rhizobia are soil bacteria that live in nodules on legume roots and fix nitrogen.
Root flare is where a tree’s trunk widens into its roots. It should sit at or just above the soil surface after planting. See Planting Containers, Shrubs & Trees.
Salinity tolerance rates how much salt a species can take, from road de-icing salt to tidal flooding. See Salt Tolerance.
Scarification means nicking or abrading a hard seed coat so that water can get in.
Seeding rate is the amount of seed sown per unit of area, written as PLS pounds per acre or PLS seeds per square foot.
Solarization means killing vegetation by trapping the sun’s heat under clear plastic.
Stratification means exposing seed to cold, moist (and sometimes warm, moist) conditions to break its dormancy. See the germination guide.
Total viability is germination plus dormant seed, meaning all the seed in a lot that is alive.
Tree shelter is a translucent plastic sleeve set over a young tree or shrub to protect it from browsing. See Choosing Tree Shelters.
Tree Tube is one of our plant sizes: a young taprooted tree, such as Paw-Paw or a hickory, grown in its own tube 10″ deep × 2.25″ in diameter and sold in clusters of 32. Plants are about 4–6″. It’s a plant, not a protective shelter.
Tubeling is a young plant grown in a deep, narrow cell, used mostly for trees and shrubs. Our 32-cell tubelings are 4″ deep × 2.25″ in diameter and our 72-cell tubelings 4″ × 1.5″.
Warm-season grass is a grass that grows mainly in summer heat and greens up late in spring.
Wetland indicator status rates how likely a species is to occur in wetlands. See Wetland Indicator Status.