11 Plants You Should Never Fertilize In Early Spring

Don’t let a few days of good weather fool you. Even if you’re seeing buds on your plants, a late freeze or unexpected cold snap can do a lot of damage. Resist the urge to wake up your garden too soon by learning about the plants you should never fertilize in early spring.

Why Some Plants Shouldn't Be Fertilized In Early Spring

Spring weather can be unpredictable. Nature signals plants when it's time to break dormancy and start growing; that's when the soil is warm and they've developed enough roots to take up nutrients in the soil. We're rushing the season when we apply fertilizer before our plants can handle it.

Fertilizing too early can encourage plants to produce weak, new top growth instead of strong root systems. Plants often produce fewer blooms, turn yellow or brown and even die. Unfortunately, fertilizer doesn’t always stay in the soil until your plants have enough roots to use it. When the ground is cold or frozen, spring rains can wash it out of your garden and into streams and other waterways, causing pollution and killing aquatic life.

Even if it remains in your soil, weeds can use fertilizer and crowd out the things you want to grow while desirable plants are still trying to get established.

When Is It Safe to Fertilize?

It’s usually safe to start fertilizing in mid-spring or later, when the ground can be worked and it isn’t too wet. This is typically after the average date of the last spring frost in your area, when the soil is warm and daytime temperatures are in the 60s.

Before you fertilize, test your soil with a DIY kit or send a sample to your county extension service to be sure it really needs nutrients. The test can tell you what to apply and how much.

In general, don't fertilize new plants until they've spent a full growing season in your garden. Other types of plants to avoid fertilizing in very early spring include most natives, drought-tolerant perennials, members of the legume family (like beans and peas), some bulbs, some root vegetables (like carrots) and evergreens with needles (like junipers and yews). Some plants just don't need fertilizer because they grow best in nutrient-poor soils. If you really want to boost some of your garden plants in early spring, improve your soil with aged compost instead of chemical or synthetic fertilizers. It helps balance the pH, improves drainage and slowly releases many good nutrients. Organic mulches are also beneficial.

Butterfly weed (Asclepias tuberosa, not shown here) is another plant that you should never fertilize in early spring. This North American wildflower, with bright orange blooms that butterflies can't resist, simply doesn't need feeding. It thrives in poor soil, and fertilizer can lead to root burn, weak and floppy foliage and fewer blooms.

Along with the types of plants we've listed above, use our round-up of eleven plants you should never fertilize in early spring, so you don’t do more harm than good.

We love lavender for its calming fragrance and flowers, which can be pale purple or violet to deep purple, purplish-blue, white and pink. (There's even a rare yellow lavender with a pine or lemony scent.) Native to the Mediterranean, lavender plants evolved to flourish in rocky, alkaline soils, so they don't need much fertilizer, if any. It can push these perennials to grow fast, but they'll develop leggy growth and weak roots that are prone to fertilizer burn, fungal diseases and rot. High-nitrogen fertilizers can also reduce their essential oils, so they're not as fragrant. If you really think you need to fertilize them, it's better to feed them sparingly with good-quality compost or a just little balanced, slow-release fertilizer, and feed them only once a year. Some growers say you shouldn't feed them at all after the first year.

Azaleas take center-stage in the spring when they open big clusters of bell-shaped or tubular blooms. Some, like Encore Azaleas, produce a few more flowers during the summer and then explode with a last, heavy bloom in the fall. Most azaleas grow best in acidic soil with a pH of 4.5 to 6 and should be mulched with pine straw, compost or other organic matter. In fertile soil, they don't need additional fertilizer; this is also true of rhododendrons. Just watch for problems like yellowing leaves, which can signal a need for nutrients like iron. If you feed your azaleas, use a fertilizer designed for acid-loving plants, but wait until their spring flowers finish and apply it when the soil is moist. Don't feed them too late in the growing season, which can promote new growth that may not have time to harden off before it's killed by cold weather.

Bees, hummingbirds and butterflies flock to the summertime blooms of bee balm (Monarda didyma), Gardeners love it for its bright, spiky flowers, but hungry rabbits and deer usually leave it alone. Bee balm thrives in consistently moist soil and grows in part sun to shade; most varieties are hardy in USDA Gardening Zones 3-9. This North American native seldom needs fertilizer and does best in soil enriched with aged compost. Fertllizer with a lot of nitrogen can encourage lots of foliage, but few flowers, and make the stressed plants more susceptible to disease.

This Black Eyed Susan (Rudbeckia hirta) almost disappears in the fast-growing mint plants around it. Rudbeckias are natives with sunny blooms that explode in late summer and come back as perennials in Zones 3-9. They're drought-tolerant sun-lovers that seldom need supplemental feeding, because they grow best in lean or poor soil. If you fertilize them in very early spring, they'll put out floppy, weak stems, but not many flowers. If it really seems necessary, feed them lightly, and just once in spring, with a balanced, slow-release fertilizer.

Most ornamental grasses don’t need fertilizing in very early spring, especially if they’re already established. Fertilizer can make them grow faster, but they’re likely to develop weak blades that fall over and the plants become more prone to stress. Most ornamental grasses grow well in nutrient-poor soil and do just fine if you ignore them; Miscanthus,also called Maiden Grass, is an exception that appreciates some fertilizer (and water).

If you’re concerned because the colors of your ornamental grasses looks faded, and they're not growing vigorously, add some compost or mulch around the bases just as new growth appears. Shown here: Carex Graceful Grasses 'Toffee Twist,' a cool-season grass in the sedge family that thrive with only a top-dressing of compost.

Most asters aren't heavy feeders and don't require fertilizer, especially once they've developed good roots. For healthy plants with lots of blooms, it's usually enough to grow them in fertile soil. Fertilizers can shorten the blooming period, and high levels of nitrogen can encourage asters to put out more foliage than flowers. Top-dress them with compost or organic mulch instead. If your soil is very poor, you can give them a balanced fertilizer for flowering plants in very early spring, but stop applying it when the flowers start to open. Most asters that come in pots don't need any extra feeding at all in their first year of growth, because nutrients have already been added to the soil. This variety is 'Marie,' also sold as 'Marie Ballard'.

For late summer color, and to attract helpful pollinators, count on sneezeweed (Helenium autumnale). No, it won't really make you sneeze. The name is said to come from an old practice of drying the leaves to make snuff; users inhaled it so they'd sneeze out any "bad spirits". This perennial wildflower thrives in lean soil and rarely needs fertilizer. If you do feed it with a product that contains a lot of nitrogen, the plants respond with rangy, floppy stems that require staking. In very poor soils, you can apply a balanced, slow-release fertilizer in early spring, but it's enough to keep the soil moist and amend it with aged compost.

The true, native purple coneflower (Echinacea) is a wildflower with slender petals that curl backwards or down. Most gardeners grow perennial coneflower hybrids that have brighter blooms. Coneflowers prefer lean soil and do very well when grown with just a couple of inches of compost or mulch. It's better not to apply chemical or synthetic fertilizers in the spring, which typically result in lots of foliage and few blooms. If your coneflowers are in containers, you probably will need to feed them every few weeks during the spring and summer, since their pot-bound roots can't spread out to find more nutrients when they use up what they have.

Commonly called pinks, Dianthus are perennials that don't need much fertilizer, if any; work a little compost into their soil instead. They react badly to products with a lot of nitrogen, producing fragile, lanky stems at the expense of flowers. You can give pinks in pots a little balanced, slow-release plant food or bone meal once they put out new growth, but plants in the ground typically fare better without it. In-garden pinks don't need much more than slightly alkaline soil that drains easily. This variety is 'EverLast (sic) Red+Pink,' also sold as 'Everlast Burgundy Blush Red and Pink'.