Will Epsom Salt Give Roses Bigger Blooms As The Fall Weather Rolls In?

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As the air grows cooler, your trusty rose bush with its vibrant blooms may begin to stall. Will a sprinkle of Epsom salt help give roses that added boost to finish the season strong? The answer is: Maybe. 

Some gardeners laud Epsom salt as a miracle fertilizer that'll do wonders for avocado trees. It could also give you lush hydrangea blooms if you're careful. You might be more familiar with Epsom salt for soothing sore muscles in the bathtub. But, as a good source of magnesium sulfate, in some cases, it might help enrich soil — especially sandy, acidic soil that's magnesium deficient. It may also make blooms bigger and better. 

Scientists have yet to prove how effective Epsom salt truly might be in helping plants, so know if you try this trick, you're relying largely on word of mouth. It's worth pointing out that Epsom salts don't actually contain the fertilizing components that most roses crave, like nitrogen or phosphorus, so it's unclear whether it will truly give roses a boost. Still, when used in moderation, it's unlikely to hurt your roses. If you'd like to try it, why not? Giving it a shot requires little expense or trouble. To test this out, all you need is some Epsom salt and water. It might be helpful to get a soil test before you apply anything to your plants.

Grab Epsom salt from your bathroom or you can buy one marketed for the garden, like Envy organic magnesium sulfate plant food. Before you get started, a word to the wise: Don't use too much Epsom salt at the base of your rose bushes. Too much salt can make your soil salty, both literally and figuratively, and put your roses in a bad mood. Salty soil means plants can't absorb water all that well. It might even get in the way of your plants getting needed calcium. Also, if you get too much Epsom salt on the leaves of your roses, it may cause yellowing or browning.

So the best rule of thumb is to go easy. You can dilute 1 tablespoon of Epsom salt into a gallon of water. Water your roses this way every couple of weeks in the fall. You can also apply salt directly to the base of the plants, using say a teaspoon for every foot of growth for the plant – or a half a cup for large, established roses. Rain water or regular watering will dissolve Epsom salt and let it seep into the soil. 

If you want to really give roses a boost and try for more vibrant, larger blooms, instead of (or in addition to) Epsom salt, think about adding organic compost or mulch this fall. These provide valuable nutrients to the soil and can help improve drainage, too. And even though it's autumn now, your roses might be bigger and bolder come springtime.