March is one of those months where the weather can’t quite decide what it wants to do. One day, it’s warm and sunny, and the next, you’re questioning all your life choices as the wind stings your face. But despite the mood swings, it’s time to get moving in the garden! If you’re new to gardening, here’s what you should be thinking about this month.

Start Seeds for Vegetables & Flowers

If you want homegrown tomatoes this summer or a garden bursting with colorful flowers, now’s the time to start seeds indoors for warm loving plants. (Trust me, future you will be so grateful when you’re picking tomatoes straight off the vine.) Warm-season crops like tomatoes, basil and many annual flowers need a head start indoors under grow lights (I find LED lights work perfectly ok for this too). If you haven’t started yet, don’t worry—you’ve still got time!

Here is a list of when to start a few of those:

• Tomatoes
• Basil
• Peppers
• Marigolds
• Cosmos
• Amaranth

Spring Cleaning... for the Garden!

We all know about spring cleaning inside the house, but your garden needs some love too. March is the perfect time to clean up flower beds, remove any dead plant material from last year, and tidy up your containers. (If you’ve ever neglected a pot all winter and found a mysterious sludge inside, you know why this is necessary.) Clearing out the old makes way for the new, and your plants will thank you for it!

Prune Shrubs (But Not the Wrong Ones!)

If you have roses or hydrangeas, now is the time to give them a trim—but not all hydrangeas! Some hydrangeas bloom on old wood, meaning if you cut them back now, you’ll be accidentally saying goodbye to flowers this year. (We’ve all made this mistake at least once… or twice.) Generally, hydrangeas that bloom on new wood—like panicle and smooth hydrangeas—can be pruned now, while others should be left alone. 
March is my preferred month for pruning my lovely hydrangea hedge, this is no quick process either, I like to take my time, looking at the established shrubs from all angles to give them the best pruning possible, as long as I have a sharp pair of pruners, I am good to go.

Roses can be intimidating, but they’re actually pretty resilient. The key to pruning is knowing when to do it and how to make the right cuts.

The general rule is to prune roses in early spring, right as the buds start swelling but before new leaves fully emerge. In Central Indiana, this is usually sometime in March, but it depends on the weather. A good trick? Prune when forsythias (those bright yellow flowering shrubs) start blooming—that’s your natural cue!

How to Prune Roses

1. Gather the Right Tools

• Sharp bypass pruners (clean and sanitized to prevent disease)
• Thick gloves (because those thorns are not forgiving
• A small saw or loppers for thick canes

2. Remove Dead or Diseased Canes

Look for dark, shriveled, or blackened stems. These are dead and should be cut all the way back to healthy tissue.

3.    Shape and Thin Out the Plant

• Aim for an open vase shape—this improves air circulation and reduces the risk of disease.
• Remove any weak or crossing branches (they can rub and cause wounds).
• Cut just above an outward-facing bud at a 45-degree angle. (This encourages growth outward, not inward.)

4.    Cut Back to the Right Height

• Hybrid teas & floribundas: Prune back to about 12–18 inches for a fresh, vigorous start.
• Shrub roses: Just remove the oldest or weakest stems and lightly shape.
• Climbing roses: Only prune dead/damaged branches in spring—major shaping is best done after their first flush of blooms.

5.    Clean Up

• Remove any pruned branches from the ground to prevent disease.
• If you have trouble with black spot or fungal issues, consider spraying a dormant oil or fungicide after pruning.

Wake Up Those Dahlia Tubers

If you stored dahlia tubers over the winter, it’s time to do a final check on them and start waking them up for the growing season. If you want earlier blooms, start them indoors in pots about 4-6 weeks before your last frost date (Mid March to early April for Central Indiana). If you don’t mind waiting until later in the season, you can plant tubers directly outside once the soil warms to at least 55°F (late April or early May).

First things first—pull them out of storage and take a good look. Are they firm and plump? Perfect. (They might look a little shriveled, and that’s okay, but if they’re completely dried out like an old raisin, they’re probably done for.) If you see any mushy or rotting spots, you can try cutting them away, but if the whole tuber is soft and gross… let it go.

Now, if you’re eager to get a head start on blooms, you can pot them up indoors about four to six weeks before your last frost. Grab a good size container (About a gallon in size)—something with drainage, like a nursery pot or a plastic bin with holes. Fill it with a light, well-draining potting mix. Nothing fancy, just something that holds moisture without getting soggy.

Place the tubers in the soil, lay them sideways and cover them completely about 2-3” deep. If you don’t see eyes yet, don’t panic—they’ll show up soon. Now, put them in a warm spot, around 65-70°F, at this point, they don’t need light yet.

Here’s the part where you have to resist the urge to water them too much. Dahlia tubers are dramatic—if they’re too wet before they start growing, they might just rot instead. Keep the soil just barely damp and wait for little sprouts to appear. In about two to three weeks, you should see tiny green shoots emerging. (This is the exciting part!) Once you see the growth peeking thru the soil, they will need 12-14 hours of a good quality light (Grow lights).

Once those sprouts get going and the outdoor temps are consistently above 55°F at night, it’s time to think about moving them outside. But hold on—you can’t just plop them into the garden right away! They need to be hardened off, which means slowly introducing them to the outside world over the course of a week. 
And that’s it! Not too tricky, right? Just a little patience, a little restraint with watering, and you’ll be rolling in dahlias by summer.

Check Out Local Gardening Events

March is a great time to get inspired! Look for seed swaps, gardening workshops, or early plant sales from your local Master Gardener groups or garden centers. Not only can you snag some cool plants and seeds, but you’ll also meet fellow plant-loving people who totally understand why you’re already daydreaming about summer flowers.
Spring is almost here, and March is the perfect time to get your garden ready for the season ahead.

Happy Gardening friends!

This blog was written by Roxana Snedeker, if you'd like to find her on socials, you can find her as @soilandmargaritas.