Roses are the picture of health when the leaves are slightly or fully glossy, and the flowers are bright, and there is no damage to the foliage or the roses themselves.
Appearance will vary depending on the type of rose and the cultivar you choose, but you’ll be able to tell instantly if your roses like their position, the soil, the weather, and how much water they get.
All of these factors contribute to healthy growth and vivid blooms, but you can help your rose by feeding it with fertilizer.
What is Fertilizer?
Fertilizer has two purposes: improving the overall quality of the soil, and providing a plant with nutrients which will increase its growth and fruit or flower production.
Used all over the world, fertilizer is integral to both farming and gardening.
Fertilizer has been in practice since we first started farming instead of just hunting or gathering food, and some techniques have largely remained the same, and some we’ve developed more recently.
We’ve gotten better at realizing exactly what plants will thrive on, and what nutrient supports a different type of growth.
Getting the balance right for different kinds of plants — as each has a different requirement — has meant that we can grow much healthier plants. It also increases the amount of flowers and fruit, as well as making them much bigger.
Why is Getting Fertilizer Right So Important in Growing Roses?
We’ve been growing roses for centuries, not just for their captivating beauty, but for medicinal and culinary purposes, and we’ve gotten very good at it.
Over the centuries, humans have bred roses to be bigger, to be more fragrant, to produce more rose hips and grow differently, from climbers to standard roses.
What helps in all of this is feeding the plant itself. While genetics help determine how the plant grows, what kind of flower it will have, and how many blooms it should produce, fertilizer helps support the growth overall.
This also helps the plant produce better roses and more blooms, as they have more energy to do so.
It’s important not to overfeed plants, as this tends to result in leafy growth and fewer flowers than the plant should produce. Overfertilizing the plant will lead to an imbalance in nutrients, and can make it more vulnerable to pests and disease.
Fortunately, you can keep track of when you last fed your plants easily.
Nutrition in Plants
Like any living thing, plants need nutrients in order to grow properly. There are two types: macronutrients, and micronutrients. The former is those that the plant needs in abundance, and the latter is what they need in small amounts.
The three big ones to remember are nitrogen (N), phosphorus (P), and potassium (K). These are also included in compost, and different amounts are in different types of compost.
Nitrogen supports healthy growth, phosphorus helps support the plant to produce healthy roots and shoots. Potassium helps the plant’s flower and fruit production, as well as boosting its defenses.
The label on each fertilizer will tell you exactly how much of each nutrient makes up the fertilizer, and there are different types of fertilizer for different purposes. You can tell from the name what the fertilizer has been designed for.
It will also give you a breakdown of the chemicals, like N:P:K, and a grading after it, which corresponds to which element and how concentrated it is.
It’s always worth taking a close look at the label, as N:P:K can also mean phosphates and potash, which can be confused with phosphorus and potassium.
Plant fertilizer doesn’t just help the plant itself, but the soil and the general ecosystem within the earth, though some plants like more nutrients than others.
Roses in particular do require calcium and iron, which promote the plant’s resistance to disease by strengthening the cell walls, and helps prevent black spot from decimating the leaves.
Neither will prevent pests or diseases taking hold completely — nothing is a bulletproof option when it comes to nature — but it plays a big part in preventing them.
Different Rose Fertilizers
No matter the purpose of the plant feed, fertilizer takes two different forms: synthetic fertilizer and organic.
Organic Rose Fertilizers
Organic fertilizers have been around for a long time, since we started practicing agriculture. They are fertilizers which are made up of animal or plant matter.
Organic fertilizers tend to release the nutrients much more slowly, as it is a natural process, and this can be more beneficial for the plants as the sudden release of nutrients can shock a plant.
The best organic fertilizers for roses are mulch, manure, dried blood and bone meal, and natural Epsom salts.
Synthetic Rose Fertilizers
As you might guess, synthetic fertilizers are man-made. You’ll see the results in your plants much quicker than if you use organic fertilizers, and they can contain a mixture of natural and synthetic minerals.
Generally, synthetic fertilizers are cheaper to produce than organic fertilizers.
Some examples include Growmore, Miracle-Gro, Sulfate of Potash, and Sulfate of Ammonia.
Granular and Powder Fertilizer
Granular fertilizers come in both synthetic forms and organic materials. You can simply sprinkle the granules on the top of the soil around the plant, and water them in.
Powder fertilizers will generally need diluting — but take a look at the label, which will tell you the best way to apply the feed.
It’s best to read the label to know when to reapply, as some feeds will break down quicker than others.
There’s a little more effort required using liquid fertilizer than pellet fertilizer, in that you have to dilute it.
It’s easily done — put the measured amount into a watering can and fill it with water, making sure to stir it with a stick so that the fertilizer spreads evenly, and then water the bottom of the plant.
Try to make sure you don’t get any fertilizer on the leaves, as this will burn and kill them — it’s an ugly look!
Liquid fertilizer acts much faster than granular or pellet fertilizer.
Pellet fertilizers are one of the most popular types, as you can sprinkle them on top of the soil, and tend to be the most environmentally friendly type. They are a slow release, but they’ll help both the soil and the plants.
It’s worth noting that you should always be careful in choosing fertilizers, as some can do more harm than good to the environment.
It’s always best to go for organic fertilizers where you can, those which won’t harm beneficial insects or that will do any harm if they get into water supplies.
Not just for these important reasons, but if you have pets or children, there’s always a chance these can be ingested, so go for pet-safe fertilizers, and keep an eye on those curious hands and paws!
What is the Best Fertilizer For Roses?
There’s nothing to say that you can’t use either, as a combination of both fertilizers can help, so long as you don’t overfeed your roses.
Roses are hungrier plants, and they need the most fertilizer during the flowering season, which takes up a lot of energy from the plant.
You can also use fertilizer just before you plant roses, like manure or bone meal. Both can be applied to the bottom of the planting hole, but be careful with manure, as if it touches the roots of the plant, it will burn them as it’s very strong!
You can get specially formulated rose fertilizers, which take out the guesswork, and it helps prevent changing the soil’s composition and the threat of it becoming unbalanced.
How to Make Your Own Rose Fertilizer
If none of those sound like good options, seaweed, and nettle fertilizers are good choices.
You can make your own nettle fertilizer — pop around 1 kg nettle leaves into a 2 gallon bucket and fill it with water. The longer you leave it — and this should be at least 2 weeks — the better the fertilizer.
When it comes to diluting it, you’ll need to use a ratio of 10:1.
You can also do this with comfrey leaves, but be aware of the smell — it’s pungent! To make a comfrey fertilizer, use 1 kg of comfrey leaves to 3 gallons of water, and seal the top of the bucket for 6 weeks. You don’t have to dilute a comfrey fertilizer.
Most plants also like seaweed fertilizer, including roses. I don’t recommend you make seaweed fertilizer yourself, as harvesting seaweed can be damaging to the environment — but it’s readily available from most retailers.
How to Fertilize Your Roses
Depending on the type of fertilizer, this will dictate exactly how you should apply it to your roses.
You should always wear gloves when handling fertilizer, and perhaps even protective glasses or a mask, depending on the type. You can’t be too careful when it comes to chemicals.
Broadcasting and Banding
These two techniques are for applying granular or pellet fertilizers. You can top-dress the soil, which is sprinkling the feed directly onto the surface of the soil that the plant sits in, and water it in.
Banding is where you place the fertilizer 2 inches to the side of the plant.
Deep Soil Application
This is also known as base dressing, where you apply the fertilizer before you put the plants or seeds into the soil, in the bottom of the hole.
It’s a fuss-free way of providing the right nutrients into the soil, as you’ve already dug the hole. Just be careful to keep the fertilizer at least a little way from the roots.
Liquid fertilizers come in two forms: where you mix the fertilizer into a watering can, known as watering on, or you apply it to the leaves, known as foliar feeding. Both need diluting, but the label will tell you exactly how much you need, and if it’s suitable for roses.
You should do neither when the sun is on the plant, as this can scorch the plant and damage it.
Liquid fertilizers are good for a “quick fix”, if you notice that the plant seems to be lacking something — they work much faster than slow release fertilizers.
When Should You Feed Roses?
This depends on the type of roses you have. Essentially, for most roses, they need feeding twice per year with a specially-formulated rose feed.
The first time is when the leaves are nearly fully open, and after feeding, you should mulch the soil to improve its quality. This will help the plant produce the best roses possible.
The second feed comes after the first flowers of the season finish, which will help encourage the plant to produce more roses.
You only need to feed the second time for roses that will flower more than once per season.
Feeding your roses is one of the best things you can do to encourage the plants to be healthy and beautiful, as well as deadheading dying or dead blooms.
Again, it’s important to stress here that you shouldn’t overfeed your roses. Too much of a good thing will often cause a whole new set of problems.
How Fertile is Your Soil?
This is a factor in any plant growth, regardless of species. Getting the soil right is the first step to a healthy plant.
It’s worth testing your soil with a pH testing kit, to see if it’s alkaline or acidic. You can also broadly tell by what plants grow well in your garden and where — as they thrive in different levels.
Different plants require different pH levels — some types like acidic soil, which some like alkaline soil.
Roses need to be in soil that has a pH between 6 – 6.5. If your soil is nowhere near this, you can grow roses in pots instead, which allows you to control the pH by using the right compost.
If the soil is somewhere near the pH, but it doesn’t fall between those two levels, you can adjust it with the right fertilizer and compost, but this will take time.
It’s also worth looking at the soil itself. Does it look “thin”, or dust like? Crumble it between your fingers. How much organic matter has it got? Is it full of dead leaves, rotten bark? If you dig a small hole, will you see any worms? Worms are a great sign that your soil is healthy.
You can improve the quality of the soil by adding mulch and compost, but you’ll need to make sure you’re adding the right type, as you don’t want to change the pH where it doesn’t need adjusting.
You’ll be able to see this on the label.
Some plants require a better quality soil than others. In terms of roses, the better quality of the soil. The “thicker” it is, generally the darker, the better your roses will grow.
How to Tell When Your Roses Lack the Right Nutrients
The best way to tell if your roses are suffering is to take a good look at the leaves. If you haven’t had a lot of extreme weather lately and the leaves are a strange color, something’s up.
Yellow leaves can indicate there’s not enough nitrogen in the soil.
Grayish-green leaves suggest there’s not enough phosphorus, and if the margins of the leaves are brown, the roses really need some potassium.
Before you run for the fertilizer, make sure that the leaves aren’t trying to tell you something else. Your roses may be suffering from pests, from temperature changes, or inadequate or uneven watering levels, and the plants are struggling to cope.
Looking at the leaves of the plant is the best way to tell if your plant is happy, or if there’s something else you could do to make it healthier.
How Much Fertilizer Should You Give Roses?
How much fertilizer you need to use entirely depends on the fertilizer you choose. The labels will always tell you exactly how much you need to apply, and when.
There are general rules, but always follow the labels for best results. When it comes to applying compost, 2-3 inches is a thick enough layer. Less than that, and it’s not really worth applying.
It’s better to apply more compost in a concentrated space, rather than spreading a thin amount over a larger area, as the soil won’t benefit as much.
Make sure to water in any liquid fertilizer properly. Pellet fertilizers can be planted a little deeper than the surface, but they don’t need watering unless the roses need water.