15 Tasks to Do in March for a Flourishing Spring Garden

In the blurred boundaries between winter and spring, March offers unique opportunities to do the tasks that lay the foundation for a thriving garden season. You can build new beds, start seeds indoors, prune perennials, divide tubers, and take care of various cleanup tasks before the rush of spring. 

Even if there is still snow on the ground or frosts in the forecast, most of these garden tasks are doable for growers in zones 5 and warmer. Southern zones have even more possibilities for early planting, preparation, and harvests.

Let’s dig into 15 gardening tasks to accomplish in March!

15 Garden Tasks to Prepare for Spring

The steps you take in late winter and early spring lay the groundwork for an abundant season. If you take care of these tasks now, you won’t have to worry about them when the weather warms, and you have much more to do.

Build New Beds

Both spring and fall are great times to build new beds. These shoulder seasons mean less overall garden maintenance and more time to focus on the infrastructure of your landscape. If you want to expand your growing space this year, March is ideal for constructing new raised beds for vegetables or establishing in-ground beds for perennials.

Birdies Raised Beds are my personal favorite because they are aesthetically pleasing, super durable, and easy to set up without any construction skills. Unlike wooden beds, these metal beds are designed to last for decades. The kit comes with everything you need to set up a new raised bed in an hour or less, including customizable shapes and sizes for your specific garden area. 

Once you’ve built a raised bed, use your free time to fill it before the season starts taking off. You can save money by starting the bottom layer with logs or sticks, then adding three to four inches of leaves or straw. Spend the bulk of your budget on quality potting mix or topsoil that is rich in organic matter. This should fill the upper four to six inches of the raised bed to prepare it for planting.

Test Your Soil

March is a good time to address the task of amending your soil. Soil testing is crucial for understanding the exact nutrients that are available to your plants so that you can fertilize and amend accordingly. It is pointless to waste money and time applying fertilizers or minerals that your plants don’t actually need. A professional soil test tells you what is in your soil, including the levels of nitrogen, phosphorus, potassium, and micronutrients. 

If you’ve struggled with nutrient deficiencies or plant problems in the past and you couldn’t figure out why, an annual spring soil analysis will help you properly diagnose the issue. For example, your results may indicate that the soil is low in calcium, which could explain why your tomatoes have been struggling with blossom end rot.

An amendment of dolomite lime or ground oyster shell could help remedy the problem. Without a soil test, you may feel like you’re throwing pasta at the wall in a guessing game.

Spread Mulch

If you didn’t spread mulch in the fall, or your mulch has already started decomposing, March is another opportunity to suppress weeds and nurture soil. Mulch adds a nice aesthetic to any landscape and provides tons of benefits to the plants and soil microorganisms. 

As a commercial organic farmer, deciduous leaf mulch was always my top pick because it worked so effectively at suppressing weeds and breaking down in the vegetable beds. You can also mulch with weed-free straw (but not hay).

Wood chips are great for covering pathways to prevent grass and weeds from growing in. Pine needles and sawdust should only be used to mulch acid-loving plants like blueberries and rhododendrons because they lower the soil pH with time.

Mulch can be spread up to four to six inches deep in some areas, depending on your goals. However, take note that deep dense mulches like straw may cause the soil to warm up slower in the spring. If you live in a cold area, hold off on mulching until the weather is hotter. In southern zones, deep straw mulch is perfect for insulating your plants from the upcoming extreme summer heat.

Start Seeds Indoors

Indoor seed sowing is the key to earlier yields and longer harvest windows, particularly in cold climates. As long as you have a bright windowsill, grow lights, or a small greenhouse, you can easily start seeds indoors to establish strong seedlings for transplanting when the weather warms. Indoor-sown plants can germinate and develop in a protected environment, so they have a head start when they’re put in the ground.

Generally, you’ll want to use your last frost date and seed packet instructions to determine the best time to sow seeds indoors. Most seed packets say to start “6-8 weeks before your expected last frost” or “sow indoors 8-10 weeks before the last frost date in spring.” You can use these instructions to count backward on the calendar from your last frost date and determine the proper planting time for your growing zone.

In addition to proper lighting, you’ll need quality seed-starting soil mix and containers for the seedlings. You can repurpose egg cartons, old nursery trays, plastic containers, or try out a soil-blocker. 

If you want something a bit easier to handle and reuse for seasons to come, Epic Seed Starting Trays offer rugged durability and specially designed root-pruning to promote strong plant establishment. The sizes include:

• Epic 16 Cell Seed Starting Trays: Best for onions, leeks, scallions, herbs, and greens
• Epic 6 Cell Seed Starting Trays: Great for brassicas and tomatoes  
• Epic 4 Cell Seed Starting Trays: Ideal for tomatoes, peppers, squash, and cucumbers

My favorite thing about the Epic trays is the large finger holes at the bottom of each cell that make the plants extra easy to remove at the time of transplanting. 

Whatever seed-starting setup you choose, be sure not to start your seeds too early or too late. If you sow indoors too early, the plants may get rootbound or overgrown by the time the weather is warm enough to plant outside. But if you start too late and you live in an area with a short growing season, your crops may not have enough time to mature and yield to their fullest potential.

Sow Cold-Tolerant Seeds Outdoors

For zones six and warmer, March is typically a great opportunity to direct sow your first crops of the season. For cold-tolerant varieties, you typically don’t have to wait until your last frost date to seed outside. As long as soil temperatures are around 40°F (4°C), many crops can germinate in the chill of early spring.

A floating row cover is a great way to add a few degrees of thermal protection for young seedlings outdoors. Row fabrics come in various brands and thicknesses, but most are made of woven polyethylene that allows sunlight and water to penetrate through while adding extra insulation to the seeds right around the soil level. 

Be sure to sow your outdoor seeds at the proper depth to ensure successful germination. Planting too deep often prevents seeds from germinating because they don’t have enough energy stored to reach up to the surface. But if you plant too shallowly, the seeds may get displaced by wind or water, or get eaten by birds.

As a general rule of thumb, sow seeds twice as deep as their largest dimension. For extra tiny seeds like lettuce and carrots, take care to press them in the soil and gently dust them with soil. Maintain continuous moisture until germination, and don’t allow the soil to dry out. 

In areas with lots of spring rains, this won’t be an issue, but in dry climates, March-sown seeds are still prone to dehydration. While I mostly irrigate mature plants with drip lines, I still use a hose to keep directly sown seeds thoroughly moist.

Prune Shrubs that Flower on Fresh Wood

Perennial plant pruning can be confusing for beginners. Should you cut them back in the fall or in the spring? One easy way to determine the answer is to consider when the shrub produces its flowers.

Plants that flower on fresh or new wood tend to flower in summer or in fall. As these shrubs come out of dormancy around March, they are focused on developing their leaves. The flower buds don’t develop until later in the season. A fresh haircut can promote new growth and lots of buds for an extra beautiful floral display in the summer.

In contrast, plants that flower on old wood are often the first to bloom in spring. You don’t want to prune plants that flower on old wood because you may remove the flower buds and lose the spring blooming show.

Avoid pruning any shrubs that flower on old wood, including:

• Azaleas and rhododendrons
• Clematis
• Quince
• Forsythia
• Lilacs
• Camelias
• Mock orange

Do NOT prune the above plants, or you may miss out on their spring flowering show. Shrubs that flower on old wood need to be pruned after they flower. March pruning is only recommended for perennial shrubs that flower later in the season.

Propagate by Softwood Cuttings

You may have noticed all the emerging fleshy green growth from perennial plants all around your garden. These vibrant new shoots are ideal for propagating as softwood cuttings. Cuttings are a quick and cheap way to replicate your plants, producing tons of new seedlings with almost zero investment. 

Hardwood cuttings are usually taken while plants are dormant in winter, but softwood cuttings are ideal for March propagation because they have flexible, young growth that hasn’t yet become woody.

Every plant has slightly different requirements, but propagating by cutting usually follows the same general process:

1. Start with clean, sanitized shears or pruners.
2. Find branches with fresh new shoots at least six to eight inches long.
3. Check that the shoots are green and flexible with fresh, new leafy growth.
4. Identify the nodes or the little stem bumps where new leaf buds are forming.
5. Take a cutting beneath a leaf node at least six inches back from the tip of the shoot.
6. Leave the upper two to three sets of leaves, and strip the lower leaves from the stem.
7. Repeat as many times as desired, never taking more than 1/3 of the parent plant.
8. Optionally, dip one end of the cutting in a rooting hormone.
9. Place the cuttings in water-filled glasses or in cell trays with vermiculite and peat moss.
10. Submerge the bottom of the stem three to five inches beneath the water or soil line.
11. Allow the upper leaves to stay above the surface.
12. Move cuttings to an area with bright indirect light.
13. Maintain consistent moisture until the cuttings begin forming roots.

The rooting time varies widely among different perennials. For example, spring softwood cuttings of lavender can root in just two to four weeks. Rose cuttings can root in as little as two to three weeks. But softwood cuttings of apples can take a month or more to develop new roots. 

Patience and observation are key. A great way to know that your cuttings have formed roots is to gently tug the stem and feel for a slight resistance beneath the soil line. If you are a beginner to propagation, rooting cuttings in clear glass with water allows you to visibly notice when the baby roots are strong enough to transplant.

Trim Ornamental Grasses

After a long winter of intense weather and freezing temperatures, many ornamental grasses look droopy and sad by March. If you didn’t prune your grasses in fall, early spring is an opportune time to give them a haircut. Pruning encourages a desirable shape for aesthetically pleasing landscaping while also promoting vigorous new growth. 

Use sharpened hedge shears or large pruning loppers to get the job done. All you need to do is cut the dead grass fronds back to just a few inches above the ground, or as close to the ground as the grass clump allows. Most grasses can be cut back by up to half or two-thirds of their growth. I prefer to hold sections and cut them in a gumdrop shape. The grass will grow back greener and more lush as the season continues.

If you’d like to avoid using machinery in the garden to protect overwintering insects, you can pop on a pair of garden gloves and gently comb the grass. This removes all the dead bits, leaving behind new, green growth.

Prune Back Dead or Diseased Debris and Branches

While you have your pruners out, note any herbaceous perennials you forgot to cut back in fall. Dead leaves and plant debris often create a breeding ground for pests and fungal diseases during the wet spring months. It’s important to go around the garden and prune away any branches or twigs that could serve as disease vectors.

You can also remove dead leaves from the base of your plants. While mulch is a very valuable resource, you don’t always want expired leaves lingering right at the base of growth, where they can hold in excessive moisture and hinder airflow.

If you notice any spores, mildew, or signs of disease, dispose of the plant debris in a trash can or burn pile. Do not compost diseased leaves or branches, as this could lead to more spread around the garden.

Plant Summer Bulbs

Most spring-flowering bulbs, such as daffodils, hyacinths, and crocus, are already popping up in colorful displays, but summer and fall-blooming bulbs are best planted around March. 

Bulbs are root storage structures that some species evolved to help them spread vegetatively. Instead of sprouting from new seeds every year, bulbous flowers can rapidly form colonies with their underground root structures. 

The term “bulb” usually lumps together all modified root propagation materials, including corms, rhizomes, and tubers. These structures ensure that plants can overwinter in the ground or survive indoors because they have food storage saved up to sprout again when the weather becomes more favorable. 

Wait to plant warm-climate species like dahlias until your garden is frost-free. But if the soil is workable and the nights are below freezing, you can still plant daffodils and tulips. 

Plant Onion Sets and Early Potatoes

Speaking of bulbs and roots, March is prime time for planting early onion sets and potatoes. Onion sets offer a quick start to onion or scallion production without having to start from seed. They look like baby onions that you plant directly into the garden with the roots facing down. 

You can sow onion sets very close together and harvest them early, like green onions, or space them four to six inches apart to grow full-size onions. On average, onion sets are ready to harvest in just 60 days, while onions grown from seed can take up to 80-90 days.  

Similarly, seed potatoes are actually small potatoes that each grow into a new plant. Each potato has several “eyes,” or buds, where new sprouts grow. You can “chit,” or pre-sprout your potatoes by leaving them on your countertop for a week or so before planting. You’ll want to bury the potatoes at least two to three inches deep with the buds and sprouts facing upwards. 

Both of these examples are crops that are propagated vegetatively or asexually. In other words, the new plants will be identical clones of the mother plant. In contrast, seed propagation is sexual reproduction involving the exchange of pollen from plant flowers. 

Both potatoes and onions can be grown from “true” seeds, but the process takes longer. Seed production offers more diversity, budget-friendliness, and control of the environment, but it takes longer. Propagation from established onion sets or potatoes speeds up the process but typically costs more. 

Divide Perennial Plants

Plant division is an important way to prevent overcrowding and expand your perennial garden for free. Division revitalizes growth and improves overall vigor, enhancing your garden’s appearance and reducing the risk of disease. 

Almost any established perennial plant can be divided into several smaller plants that you can give away or transplant. Avoid dividing young or newly transplanted plants, as they still need time to establish their roots. 

While the exact methodology varies across species, here are the general steps for successfully dividing perennial plants in spring:

1. Use a sharp shovel to dig a circle around the entire plant root zone.
2. Gently lift the whole plant or colony of plants from the soil using your shovel as a lever.
3. Find the clumps you wish to divide.
4. Use pruners or the side of the shovel to cut the root clump into smaller portions.
5. Ensure each division is at least 6” wide or large enough to reestablish.
6. Every division should have both roots and shoots so it can take off growing.
7. If the plant’s roots are fibrous, use your hands to gently tease apart the tangled sections.
8. If the plant has a solid crown, use a sharp knife or pruners to carefully cut them.
9. Find a nearby bed or pot, and transplant each division with plenty of space from its neighbors.
10. Replant one division in the original location.
11. Ensure the soil level remains where it was before. Avoid burying the crowns or growing tips too deep.
12. Keep divisions thoroughly watered until they get established in their new area.

Potted divisions also make excellent gifts for your gardening friends.

Fertilize with Slow-Release Organic Fertilizers

Spring amendments with compost and mulch are important ways to feed your soil for a healthy start to the season. This is also the time to add slow-release fertilizers to your planting beds. Whether you are direct seeding, transplanting, or establishing new beds, fertilizing in the spring ensures that young plants can take off with a bang.

Slow-release organic fertilizers are plant and animal byproducts that decompose into the soil over time, gradually releasing nutrients for your plants to uptake. They provide long-term nutrition without the need for constant reapplication. Better yet, these fertilizers slowly nurture young plants instead of blasting them with harsh amounts of fertility all at once.

In contrast, quick-release fertilizers are typically synthetic and supply all the nutrients right away. They can burn young plants, leach into groundwater, and cause ecological damage. While they may provide an instant boost of growth, they come with more risks for over-fertilizing and harming the fragile soil microbiology. Quick-release fertilizers also require lots of applications because they can’t provide long-lasting plant nutrition like organic fertilizers do. 

Most of these products can be mixed into the upper few inches of soil and left to work their magic with the soil microbes and available moisture. They improve fertility over time and add a nice boost to newly established or renovated garden beds.

Always read the package instructions and reference your soil tests or plant observations before applying fertilizer. When in doubt, err on the side of caution. It’s better to underfertilize and add more later rather than overfertilizing and potentially damaging your plants or harming the environment.

Check Your Irrigation System

Many regions have plenty of spring rains to keep the garden moist throughout March. This means that you’re not using your irrigation system quite yet. Make use of the downtime to check and clear irrigation lines, maintain your pumps, clean your filters, and ensure everything is running properly. You don’t want to wait until the hottest drought of the summer to address irrigation issues. 

If you don’t yet have an irrigation system, spring is an ideal time to build one. You will be more prepared for the hottest months, and you won’t have to worry about losing a bunch of crops to drought while you go for a weekend getaway. 

Drip irrigation is the most efficient method for watering crops without wasting water or causing plant diseases. It works by running thin water lines throughout the garden and delivering moisture straight to the base of your plants. No water is left to sit on the leaves and cause fungal diseases, and far less moisture is lost to evaporation from the hot sun. Once you install a drip system, you can use it to irrigate for years to come. This video has a lot more info on how to get setup quickly: 

For small-scale growers or gardeners without consistent water supplies, consider irrigating with buried clay pots. Sometimes called ollas or “oya,” these unique porous clay pots reduce watering needs by up to 70%. 

They work by slowly releasing water directly to your plant’s root zone without the risk of overwatering. Your plants can draw exactly the amount of water they need, leaving the rest of the moisture inside the pot until the soil dries out. Burying the clay pot in the soil and filling it with water allows you to leave garden beds for several days to weeks at a time without worrying about moisture. 

Thoroughly Weed Your Beds

The busyness and excitement of summer haven’t set in yet, so why not take this “off time” to thoroughly weed all your garden beds? Weeds are the bane of most gardeners’ existence, but early prevention makes weeding so much easier. If you catch weeds at the “white thread” stage, they are less likely to become a nuisance or grow into a major infestation later on. Tiny weeds are easier to remove because they haven’t yet established their root systems and are less likely to choke out your new transplants.

My favorite weeding tool is a hula hoe, also called a scuffle hoe or stirrup hoe. This long-handled tool works by walking alongside your head and shuffling the hoe back and forth in the upper one to two inches of soil. It cuts away any weeds right at their base, essentially beheading them so they can’t grow any further. This is beneficial because it doesn’t disturb the soil too much, and it only takes five to ten minutes to sweep through a small garden.

Most crops struggle when they are competing with aggressive neighbors. If you take care of weeds now, your summer harvests will certainly thank you!