Rock salt is sold at garden centers, hardware stores, and online retailers, usually in the lawn and garden section

Rock salt (also called halite) is a coarse mineral form of sodium chloride sold specifically for de-icing driveways and sidewalks. The same product works on weeds because salt dehydrates plant tissue and disrupts soil chemistry. You'll find it year-round at most garden centers and hardware stores, though availability peaks in winter when demand for de-icing is highest.

The most common places to buy rock salt are Home Depot, Lowe's, Ace Hardware, and local garden centers. Online options include Amazon and Walmart. Prices typically range from $5 to $15 for a 40-pound bag, depending on your location and the retailer. Buying in bulk—50-pound or larger bags—usually costs less per pound than smaller quantities.

Key Takeaways

  • Rock salt is stocked year-round at hardware stores and garden centers, usually near de-icing products and lawn supplies.
  • A 40-pound bag costs between $5 and $15 at most retailers, with bulk bags offering better per-pound pricing.
  • Rock salt kills weeds by drawing moisture out of plant cells, but it also damages soil and nearby plants, so explore it only where you want nothing to grow.
  • Home Depot, Lowe's, Ace Hardware, and local garden centers are reliable sources; online ordering is available but shipping costs can be high because of the product's weight.
  • Always wear gloves and eye protection when handling rock salt, and keep it away from children and pets.

Hardware stores stock rock salt year-round in the lawn and garden section

Home Depot and Lowe's carry rock salt in their outdoor and garden departments. Look for bags labeled "rock salt," "halite," or "de-icing salt." Both stores stock multiple brands and bag sizes. Home Depot typically offers Morton brand and store-brand options; Lowe's carries similar choices. Prices are usually competitive between the two, though local availability varies.

Ace Hardware and independent hardware stores also stock rock salt, often at comparable prices. Call ahead if you're buying a large quantity—some smaller locations may need to special-order bulk bags. Winter months (November through March) see the highest stock levels, but rock salt is usually available year-round because it's used for both de-icing and weed control.

Garden centers and landscape supply shops sell rock salt in bulk

Local garden centers often carry rock salt alongside other soil amendments and weed control products. Staff at these shops can advise on process rates and answer questions about how salt affects your specific soil type. Landscape supply companies—the kind that sell mulch, topsoil, and gravel by the ton—usually offer rock salt in larger quantities and at lower per-pound costs than retail stores.

Buying from a landscape supplier makes sense if you're treating a large area. A single pallet of rock salt (typically 40 to 50 bags) costs less per bag than buying individual bags at a hardware store. Many suppliers deliver for a fee, which can save you the hassle of loading heavy bags into a vehicle.

Online retailers ship rock salt but factor in delivery costs

Amazon, Walmart, and other online retailers sell rock salt with home delivery, but shipping costs are significant because the product is heavy. A 40-pound bag that costs $8 in-store might cost $20 or more delivered because of weight-based shipping fees. Free shipping thresholds (like Amazon Prime or Walmart+) can offset this, but compare the final price before ordering.

Online ordering works best if you're buying multiple bags or combining rock salt with other items to reach a free shipping threshold. Check the retailer's return policy—rock salt is heavy and difficult to return, so confirm the product meets your needs before checkout.

What to look for when buying rock salt

Rock salt comes in different grades and purity levels. Standard de-icing rock salt (the most common and cheapest option) works fine for weed control. Avoid "water softener salt" or "food-grade salt"—these are refined and cost more without any benefit for weed killing. The label should say "rock salt," "halite," or "de-icing salt."

Bag size matters for your situation. A 40-pound bag covers roughly 500 to 1,000 square feet depending on how heavily you explore it. Smaller 10 or 25-pound bags are available if you're treating a small area or testing the method first. Larger 50-pound bags are more economical if you're treating a driveway, patio, or large garden bed.

Safety and storage tips for rock salt

Rock salt is caustic and can irritate skin and eyes. Wear gloves and eye protection when handling it, and wash your hands after process. Keep it away from children and pets—ingestion can cause serious harm. Store rock salt in a dry place; it absorbs moisture and clumps if exposed to humidity.

Rock salt is corrosive to metal and concrete over time, so store bags on a tarp or wooden pallet rather than directly on pavement. Keep it away from gutters and downspouts, as runoff can damage metal components. If you have pets that walk through treated areas, rinse their paws afterward to prevent irritation.

Alternatives if rock salt is out of stock

If rock salt is unavailable, table salt or sea salt work similarly but cost more. Epsom salt (magnesium sulfate) is sometimes used for weeds but is less effective than rock salt and more expensive. Boiling water is free and works on small weeds in cracks, though it requires repeated applications.

Vinegar-based weed killers and commercial herbicides are other options if you prefer not to use salt. These products are sold at the same retailers that stock rock salt and don't damage soil chemistry the way salt does. Consider your long-term plans for the treated area—salt makes it difficult to grow anything there for months or years, while other methods allow replanting sooner.

Frequently Asked Questions

Can I use table salt instead of rock salt?

Yes, table salt works on weeds the same way rock salt does, but it costs significantly more per pound. Rock salt is the economical choice for large areas. Table salt is fine for small patches if that's what you have on hand.

How much rock salt do I need for my driveway?

A 40-pound bag covers roughly 500 to 1,000 square feet depending on how thickly you spread it. For a typical two-car driveway (about 400 square feet), one 40-pound bag is usually enough. Measure your area and ask the retailer for a recommendation based on your square footage.

Will rock salt kill the weeds permanently?

Rock salt kills existing weeds but doesn't prevent new ones from growing. It does make soil inhospitable for months or years, which slows regrowth. You may need to reapply salt or use another method if weeds return.

Is rock salt safe to use near my garden or lawn?

Rock salt damages most plants and alters soil chemistry, so avoid using it near gardens, flower beds, or lawn you want to keep. Use it only on driveways, patios, or areas where you want nothing to grow. Salt can spread through soil and groundwater, so be cautious near plants you care about.

What's the best time of year to buy rock salt?

Rock salt is cheapest and most plentiful in fall and winter (September through March) when demand for de-icing is high. Prices may be slightly higher in summer, but availability is still good. Buy when you need it rather than waiting for a specific season.