March is the month when gardens start waking up.
After months of cold and dormancy, plants are finally preparing for a season of strong growth and beautiful blooms.
But just like people need a good breakfast to start the day, plants need the right nutrients to thrive.
Fertilizing in March helps give plants the boost they need as they break out of their winter rest and begin stretching toward the sun.
Not all plants need fertilizing at this time, though, and using the wrong fertilizer—or feeding at the wrong time—can do more harm than good.
That’s why it’s important to know which plants will benefit from a nutrient boost this month.
Here are the key plants that should be fertilized in March and how to do it the right way.
Roses
Roses are among the most rewarding plants to grow, but they demand a little extra care to reach their full potential.
March is the perfect time to fertilize roses because they are just starting to emerge from their winter dormancy.
Feeding them now gives them the nutrients they need to develop strong stems, lush foliage, and abundant blooms in the months ahead.
Timing is everything when it comes to fertilizing roses.
If you live in a warmer climate where roses never fully go dormant, you can begin fertilizing in late February or early March.
In colder regions, it’s best to wait until you see signs of new growth—tiny red or green shoots emerging from the stems—before applying fertilizer.
Feeding too early can encourage tender new growth that might be damaged by a late frost.
Choosing the right fertilizer is essential for healthy roses.
A balanced fertilizer with equal parts nitrogen, phosphorus, and potassium (such as a 10-10-10 or 12-12-12 formula) provides overall nutrition.
However, many gardeners prefer a rose-specific fertilizer that contains extra phosphorus, which promotes larger, more vibrant blooms.
Look for a fertilizer labeled 5-10-5 or 6-12-6 to encourage flower production.
For organic gardeners, composted manure, fish emulsion, or alfalfa meal can provide slow-release nutrients that keep roses healthy throughout the growing season.
Applying fertilizer correctly is just as important as choosing the right kind.
Scatter granular fertilizer around the base of each rose bush, keeping it a few inches away from the stems to prevent burning.
Water deeply after applying to help nutrients reach the roots.
If using liquid fertilizer, mix it according to the package instructions and apply it directly to the soil.
Avoid getting fertilizer on the leaves, as this can cause leaf burn, especially on hot, sunny days.
In addition to a good feeding, roses appreciate a layer of organic mulch around their base.
Mulch helps retain moisture, suppress weeds, and gradually enrich the soil as it breaks down.
After fertilizing, apply a two- to three-inch layer of mulch, such as shredded bark or compost, leaving space around the stems to prevent rot.
Feeding roses in March sets the foundation for a spectacular blooming season.
With the right nutrients, they will produce healthier leaves, stronger stems, and bigger, more colorful flowers that last well into summer.
A little effort now will reward you with a garden filled with fragrant, show-stopping blooms.
Hydrangeas
Hydrangeas are known for their large, stunning blooms, but they need the right nutrients at the right time to reach their full potential.
March is an important month to fertilize hydrangeas, as they begin waking up from winter and preparing to grow.
A well-timed feeding in early spring helps produce lush foliage and larger, more vibrant flowers later in the season.
The type of hydrangea you have determines how and when to fertilize.
Bigleaf hydrangeas (Hydrangea macrophylla), which include mophead and lacecap varieties, form their flower buds on old wood.
These should be fertilized lightly in early spring to support healthy foliage without encouraging excessive growth that could weaken the plant.
Panicle (Hydrangea paniculata) and smooth hydrangeas (Hydrangea arborescens) bloom on new wood, meaning they can handle a stronger feeding in March to promote fresh growth and more abundant flowers.
Using the right fertilizer is key to keeping hydrangeas healthy.
A balanced fertilizer, such as 10-10-10 or 12-4-8, provides essential nutrients for overall growth.
If your goal is to enhance the flower color of bigleaf hydrangeas, adjusting the soil pH can help.
For blue flowers, apply an aluminum sulfate solution or a fertilizer specifically designed for acid-loving plants, such as one formulated for azaleas and rhododendrons.
For pink flowers, add garden lime to raise the pH.
When applying fertilizer, scatter granular feed evenly around the base of the plant, keeping it a few inches away from the stems.
Water thoroughly after fertilizing to help nutrients reach the roots.
If using a liquid fertilizer, mix it according to the instructions and apply every two to four weeks during the growing season for best results.
Mulching after fertilizing helps retain moisture and keeps soil temperatures stable as the plant begins growing.
A two- to three-inch layer of compost, pine bark, or shredded leaves improves soil quality over time and provides a slow-release source of nutrients.
March fertilization gives hydrangeas the energy they need to produce larger, healthier blooms when summer arrives.
By feeding them now, you ensure they have everything necessary to put on a spectacular floral display in the months ahead.
Tomatoes
Tomatoes are one of the most rewarding crops to grow, but they need the right nutrients from the start to develop into strong, productive plants.
March is a crucial time to begin fertilizing tomato seedlings, as many gardeners start their plants indoors before moving them outside in late spring.
Fertilizing at the right time and with the right nutrients ensures that your seedlings grow sturdy stems, healthy leaves, and a well-developed root system.
Young tomato seedlings don’t need fertilizer immediately after sprouting.
For the first couple of weeks, they rely on the nutrients stored in their seeds.
However, once they develop their first set of true leaves—usually about two to three weeks after germination—it’s time to start feeding them.
At this stage, tomato seedlings require a gentle, diluted fertilizer to avoid overwhelming their delicate roots.
A balanced, water-soluble fertilizer with equal amounts of nitrogen, phosphorus, and potassium (such as a 10-10-10 or 5-5-5 formula) is ideal for early growth.
If you prefer organic options, fish emulsion or compost tea provides a gentle but effective boost.
When fertilizing, it’s important to use a weak solution to prevent burning the young plants.
Dilute the fertilizer to half strength and apply it every 10 to 14 days.
Pour the solution directly onto the soil rather than spraying the leaves to avoid damage.
As the seedlings continue to grow, you can gradually increase the concentration and frequency of feeding.
In addition to fertilizing, tomato seedlings need proper light, warmth, and moisture to thrive.
Keep them under grow lights or in a bright, sunny window for at least 12 to 16 hours a day.
Maintain a consistent temperature between 65-75°F to encourage steady growth.
Water regularly, but avoid keeping the soil too wet, as overly damp conditions can lead to damping-off disease.
March fertilization helps prepare tomato seedlings for the transition to outdoor planting later in the season.
By feeding them correctly now, you ensure they develop strong stems, healthy roots, and vigorous growth that will lead to a bountiful tomato harvest in summer.
Citrus Trees
Citrus trees, whether grown outdoors in warm climates or indoors in containers, require proper feeding to produce sweet, juicy fruit.
March is a critical month for fertilizing citrus trees, as they begin to wake up from winter dormancy and prepare for a new season of growth.
Providing the right nutrients at this time ensures strong branches, lush green leaves, and abundant flowers that will turn into fruit later in the year.
Citrus trees are heavy feeders and require a fertilizer that supplies key nutrients, particularly nitrogen, phosphorus, and potassium.
Look for a citrus-specific fertilizer with a formula like 6-4-6 or 8-3-9, which is designed to support both foliage and fruit production.
Additionally, citrus trees need micronutrients like magnesium, iron, and zinc, which help prevent deficiencies that can lead to yellowing leaves and poor fruit quality.
When applying fertilizer, spread it evenly around the drip line of the tree—the outer edge of the canopy where rain naturally falls.
Avoid placing fertilizer directly against the trunk, as this can cause root burn.
Water thoroughly after feeding to help nutrients soak into the soil and reach the roots.
For potted citrus trees, use a liquid citrus fertilizer diluted to half strength and apply it every three to four weeks during the growing season.
Granular slow-release fertilizers can also be used for a steady supply of nutrients over time.
In addition to fertilizing, citrus trees need proper watering and sunlight to thrive.
Ensure they receive at least six to eight hours of sunlight daily and keep the soil consistently moist but not waterlogged.
If growing citrus indoors, rotate the plant regularly to ensure even exposure to light.
Feeding citrus trees in March provides them with the nutrients needed for a strong start to the season.
With proper care, they will reward you with fragrant blossoms and delicious fruit in the months ahead.
Lawns
A lush, green lawn is one of the first signs that spring has arrived.
If you want thick, healthy grass this year, March is the time to start fertilizing.
After months of cold temperatures, your lawn is beginning to wake up, and giving it the right nutrients now will help it recover from winter stress and prepare for vigorous growth.
Applying early spring fertilizer strengthens the grass, improves color, and helps prevent weeds from taking over.
Timing your lawn fertilization correctly depends on where you live and the type of grass you have.
Cool-season grasses, such as Kentucky bluegrass, fescue, and ryegrass, start growing again in early spring as temperatures rise.
Fertilizing in March gives them a head start before the peak growing season in April and May.
Warm-season grasses, like Bermuda, St. Augustine, and zoysia, take a little longer to come out of dormancy.
If you have warm-season grass, it’s best to wait until late March or early April to apply fertilizer, once the grass starts showing active growth.
Choosing the right fertilizer is just as important as timing.
For early spring feeding, a slow-release fertilizer with a balanced mix of nitrogen, phosphorus, and potassium (such as a 20-5-10 formula) is ideal.
This provides the nutrients your grass needs without overwhelming it with excessive growth too soon.
If weeds are a concern, consider using a fertilizer with pre-emergent weed control to prevent crabgrass and other unwanted plants from sprouting.
Applying fertilizer correctly ensures the best results.
Use a broadcast spreader for even distribution and apply the fertilizer when the lawn is dry to prevent clumping.
After spreading, water lightly to help nutrients soak into the soil, but avoid overwatering.
A healthy lawn also benefits from aeration, which allows nutrients, water, and oxygen to reach the roots more effectively.
If your soil is compacted, consider aerating before fertilizing to improve absorption.
Fertilizing in March gives your lawn the boost it needs to grow thick and green as temperatures continue to rise.
With proper feeding, watering, and mowing, your yard will be the envy of the neighborhood all season long.
Final Thoughts
March is a crucial month for fertilizing many plants, setting the stage for a season of healthy growth.
From roses and hydrangeas to citrus trees and lawns, feeding your plants now ensures they get the nutrients they need at the right time.
By choosing the correct fertilizer and applying it properly, you’ll enjoy stronger plants, more vibrant flowers, and a thriving garden in the months ahead.