I was thinking recently about gardening expectations. About how, if certain plants don’t do so well one year, I’m ok with that. But when other plants fail to meet my expectations, I’m decidedly more disappointed.
So if my rhododendrons aren’t blooming particularly well, I can live with that.
But if my roses are a bit lazy one year, I find myself getting so disappointed. It must be rough to be the golden child with a lot of achievement expectations placed upon you.
In the interest of saving both myself and our readers from a season of unmet rose expectations, here’s what usually works for me to get beautiful rose blooms every year.
How do we get a cascade of beautiful rose blooms all throughout the season?
You’ve probably already heard that all-too-common phrase “roses are heavy feeders.” But what does that even mean? And what exactly are they feeding on?
Let me replace that with a different mindset. “Roses love to grow.”
And for that, they need a few things, starting with nutrient-rich soil.
In addition to this, they also need plenty of water and plenty of sun. So, in my experience, whenever someone says “heavy feeders,” I try to take a more holistic look at what “food” they need, which includes sunshine, water, healthy, rich, and biodiverse soil, and fertilizer.
Why is fertilizing roses so confusing?
I agree, it gets kind of confusing quickly when you consider that we all garden in different climates, different types of soil, and with hundreds (if not thousands) of rose cultivars at our fingertips with the click of the “add to cart” button.
Then add the human element (time, effort, budget, actually remembering to do it) to all of these complex factors, and you’ll get yourself in a pickle. I remember reading an article last year in which the author was fertilizing their rose garden every two weeks. Who has time for that?
So, in this article, allow me to lay the groundwork for feeding roses for more blooms. I’ll talk about the basics, and should you want to add to that, feel free to do so.
When should we start fertilizing roses?
We can start feeding roses in mid-spring, once they’ve started to leaf out and have about 8-10 inches (20-25 centimeters) of new growth. Once you’re done with pruning the roses in spring, then fertilizing is the next step.
If you didn’t get a chance to feed them earlier in spring, and your roses are still actively growing, the second-best time is now.
For reblooming roses, giving them a boost in the form of quick-release liquid fertilizer is a good strategy between two flushes of flowers. So, you might need to reapply the fertilizer in mid-season (usually in June).
Unless you’re reading this article in late summer, in which case, you should stop feeding your roses.
I know that older advice said that you should stop fertilizing about six weeks before your first estimated frost date in the fall. But in my area, the frost dates are getting pushed further and further towards the end of the year. So I don’t think this is a reliable milestone anymore.
So it’s a good idea to allow the roses to prepare for dormancy starting in late summer and early fall. The later in the year we fertilize them, the more tender new growth we will encourage, which will only be damaged by cold snaps.
What kind of fertilizer do roses need?
For roses that are planted in the garden (so not in pots), keeping a balanced ratio is best. That means an NPK number that’s fairly balanced in the nutrients it contains.
This Down To Earth Balanced Organic Fertilizer is an ideal option.
Don’t know what NPK stands for?
NPK stands for Nitrogen, Phosphorus and Potassium, and they’re the macronutrients that play a role in plant development and health. You’ll find this number on any bottle of fertilizer. (It’s a legal requirement.)
For me, the easiest way to remember which one does what is by remembering the following phrase (it’s an old one, I didn’t make it up.)
Up, down, and all around.
Here’s what the mnemonic device means:
N (UP) – Nitrogen helps boost lush growth above ground (aka foliage);
P (DOWN) – Phosphorus is essential for root growth, as well as for good blooms;
K (ALL AROUND) – Potassium is an all-around nutrient for overall plant health.
Remember how we said that roses like to grow. So they will need all of these macronutrients in order to have healthy and robust growth. And a richly blooming rose needs to be healthy and thriving, first and foremost.
Therefore, an organic slow-release fertilizer that’s 10-10-10 or 4-4-4 would be a good choice for roses.
If you really want to pump up the blooming volume, you might want to look for one with a higher P-number, for example, a 4-8-4 fertilizer such as this Down To Earth Rose & Flower Natural Fertilizer. But, generally, that’s a good idea for the middle of the season, often around June, just when reblooming roses are taking a rest between flowering flushes.
How do I apply the fertilizer on my roses?
Generally, organic slow-release fertilizers are granules. You must read the label carefully and use the amount recommended by the manufacturer.
Producers use slightly different formulas, and they are the ones that have done the testing on their specific product.
If there’s bark mulch around the rose, try sweeping it away a bit. Then water the rose and sprinkle the feed granules around the shrub’s drip line. Finish by watering it again and moving the mulch back to its place.
The magic potion for roses: Alfalfa meal
Let’s look at feeding roses a different way, too, shall we?
I brought up my strategy of “feed your soil, not your plants” in other fertilizing guides we’ve published.
When I wrote about spring jobs for hostas, I told you about how I use lava meal to help these prized perennials grow more resilient.
When I wrote about feeding hydrangeas, we all gasped at the sight of that pitch-black, viscous liquid, which turned out to be concentrated seaweed soil conditioner.
Both of those amendments will also work to feed the soil for your roses. So if you have them, go ahead and use them (again, as indicated on the packaging).
But I want to add one more organic, plant-based feed to our arsenal: alfalfa meal.
I learned about using alfalfa pellets to boost rose health and blooming from one of my favorite gardening YouTubers, Jason from Fraser Valley Rose Farm.
Jason propagates, grows, and sells roses in British Columbia, Canada. Even though he’s a full-time rose farmer, his advice is pretty down-to-earth and achievable for us non-commercial gardeners.
He recommends using alfalfa meal to feed roses about once a month (or even less often) during the growing season.
And let me tell you that alfalfa works wonders for roses.
That’s because alfalfa is a nitrogen fixer, like all legume crops. The plant itself, during its growth process, forms nodules that fix nitrogen in the soil.
That’s particularly helpful because synthetic nitrogen (in the form of nitrate in conventional fertilizers) is water-soluble, so it tends to wash away quickly. If we use alfalfa meal, the nitrogen is available to plants when they need it, longer-term.
In addition to macronutrients, alfalfa also contains 30 other micronutrients (such as manganese, sodium, iron, zinc, copper, etc.) and amino acids.
These elements feed the microorganisms that, in turn, feed the soil. So our roses will not just get a boost of nutrients – the botanical equivalent of a caffeine energy shot – but an overall healthy growing medium. The roses will be able to absorb what they need from the soil when they need it.
I’m convinced, but how do I apply the alfalfa meal?
If you’re into brewing potions, you could brew some alfalfa tea. Just like when you make compost tea, you add the alfalfa pellets to water (again, read the packaging for quantities), let it steep for a few days, then use it to water the roses.
By “soaking” the alfalfa pellets this way, the rose roots absorb them faster.
For me, this method is a bit cumbersome. I garden in a small suburban backyard and I don’t have enough buckets or space to brew enough alfalfa tea for all of my soil.
So, I sprinkle the alfalfa meal around the base of the roses, almost like a top dressing, and then work it into the soil using my hand spade.
In order to help the pellets break down and become available faster, I always water everything thoroughly.
Can I use alfalfa animal feed as a fertilizer?
Yes, you can. It’s definitely more economical to buy it in large bags as animal feed. But you have to pay attention to three things:
One: Additives
First, there might be some additives in alfalfa animal feed (such as salt) that you don’t want accumulating in your soil. Not all brands have additives. But check that what you’re buying is pure alfalfa and nothing else.
Two: Pellet size
Secondly, the alfalfa animal feed usually comes in larger pellets or cubes, while agricultural alfalfa is smaller and finer. So if you’re buying the larger feed variety, just grind the pellets down in your hand as you sprinkle them around the base of the plant.
Three: Nitrogen content
This is something I learned from watching this interview with an alfalfa grower. The timing of the cut differs for the two uses. Alfalfa used as an agricultural fertilizer is the first batch that is picked early in the flowering stage of the alfalfa plant. This ensures a higher protein level, thus higher nitrogen.
What remains in the field for processing is turned into animal feed. As a result, the fertilizer alfalfa pellets are about thirty percent higher in nitrogen than feed alfalfa.
So, if you can, I would recommend buying alfalfa meal that has been specifically produced as a soil amendment rather than alfalfa feed.
Espoma is a well regarded and highly popular producer of organic soil amendments and fertilizers and they sell this bag of organic Alfalfa Meal here on Amazon.
One More Job for Masses of Rose Blooms: Deadheading
In addition to making sure our roses get a nice nutritious start to the growing season, there’s one more thing to do to keep them blooming: deadheading.
Deadheading is important, especially early and mid-season. Naturally, after a rose flower starts to fade, the ovary (the part where all the petals attach) will start the process of setting seed. When we’re deadheading, we’re disrupting this process and helping the rose shrub redirect its energy from seed formation to opening up new buds.
Deadheading is really easy. All we have to do is cut off the stem holding the old bloom down to the next set of leaves. If we do this regularly on repeating bloomers, we’ll get even more flowers. And hey, if you have a celebration coming, the best way to use those faded roses is sun-drying them. Then you can turn them into biodegradable petal confetti.
Mickey’s deadheading tip!
I stop deadheading my roses towards the end of the flowering season. This allows the last batch of flowers to form rosehips. I leave some for the birds to snack on over the winter months. And I harvest some for myself to use in teas. I wrote more about it in my rose fall care guide. How about you bookmark that to come back to in a few months?
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