Roses need lots of food to produce beautiful abundant blooms and the healthier the rosebush the more it will produce.
This is why it’s so important to choose the right fertilizer for your rose bushes and apply it correctly. This includes fertilizing knockout roses as they love food!
Well-fed rose bushes are also better able to defend themselves against pests and pathogens.
In this article, we discuss the best Rose fertilizer choices and share useful information on how to use them. Read on to learn more.
How Can You Choose the Best Rose Fertilizer?
Begin by understanding what all plants need to grow and thrive.
When you look at a package of plant fertilizer, you will see three numbers in the labeling.
These numbers represent the nitrogen, phosphorus, and potassium (NPK) ratio.
What Do These Three Nutrients Do?
Nitrogen (N) Supports The Development Of Shoots And Leaves
Nitrogen is naturally found in proteins. It is a nutrient which must be replenished regularly because it’s easily washed away from the roots of the plant.
Because nitrogen supports lush, green growth, it’s necessary for the production of chlorophyll.
Chlorophyll is the element enabling plants to conduct photosynthesis which converts carbon dioxide and water into sugars for feeding the plant.
You have to use just the right balance with nitrogen, especially when your goal is lots of flowers.
You want to provide enough nitrogen to fully support the plants’ green, vegetative growth without stunting the production of blossoms.
If you give your rose bushes too little nitrogen, the leaves will be stunted and yellow, and your blossoms will be small and pale.
When used correctly nitrogen supports good stem and leaf growth and allows abundant blooming.
Phosphorus (P) Supports The Development Of Roots
Phosphorus doesn’t just allow abundant blooming; it encourages it.
In addition to supporting root growth, phosphorus also encourages lots of blossoms.
Additionally, the right amount of phosphorus works with nitrogen to keep foliage and stems strong and bright.
Too little phosphorus will cause flower and leaf stems to weaken and break easily.
Leaves may fall off without enough phosphorus, and the plant may produce lots of buds which never open.
Potassium (K) Is Similar To A Vitamin And Benefits The Entire Plant
Potassium is a tonic assisting other nutrients in working well together.
It provides a boost to the immune system so your rose bush can cope with stressful conditions, such as challenging weather, insect predation, and disease.
Like phosphorus, potassium supports healthy bud development, strong stems, and leaves.
Without enough potassium, buds would not develop properly, the leaves would yellow, and stems would be weak.
What Other Nutrients Do Roses Need?
In addition to nitrogen, phosphorus, and potassium, roses also require other nutrients such as magnesium and calcium.
Magnesium promotes intense color in flowers and leaves and also boosts flower production.
More on –> (Magnesium) aka Epsom Salt for Roses
Fertilizer containing the right amount of magnesium helps prevent harmful salts from collecting in the soil.
Calcium strengthens cell walls and boosts the immune system to provide the plant with protection against insect predators, such as aphids.
Other trace elements or micronutrients helpful to roses include:
Which is Better? Organic or Chemical Rose Fertilizer?
Although roses are not picky as to whether their fertilizer is organic or inorganic, there are a few things you should keep in mind when you make your choice.
Whichever type you choose, be sure to look for all of the nutrients we’ve listed here to provide the right type of nourishment for your roses.
Seek out a balanced NPK ratio and a thorough array of macronutrients and micronutrients.
More on –> Natural Fertilizer for Roses
Pros & Cons Of Organic Rose Fertilizer
Organic fertilizers are naturally better for the environment, and they are naturally slow releasing.
Side dressing and top dressing your rose bushes with compost, manure, and other organic, biodegradable plant and animal materials is a good way to feed your roses.
Organic matter choices include:
These all-natural, organic fertilizers help improve the texture of the soil, encourage healthy microorganisms in the soil, and build up humus levels.
On the downside, the number of nutrients provided by these organic materials may be rather low.
For this reason, you’ll need to remember to add organic matter to the soil on a regular and continual basis.
Luckily, it’s very easy to keep your own compost heap or bin and make good use of organic matter such as:
- Composted yard debris
- Kitchen scraps
- Aged manure
- Lawn clippings
Pros & Cons Of Chemical Rose Fertilizer
If you prefer not to keep a compost heap or bin, you may wish to simply purchase a prepared chemical fertilizer.
These concentrates are usually quite affordable and are available in various formulations.
- Liquid, water-soluble fertilizer
- Slow-release fertilizer
- Granular fertilizer
While these types of fertilizers will provide the nutrients your roses need, there are some downsides.
For one thing, chemical fertilizers don’t condition the soil or encourage the development of friendly fauna.
You will need to take additional steps to keep your soil in good condition and to introduce and maintain the beneficial bacteria your soil needs.
Chemical fertilizers provide a big boost of nutrients all at once, but they don’t remain in the soil, instead, they wash into the water table.
If you use chemical fertilizers, set a regular fertilizing schedule and keep it.
Follow packaging directions very carefully when using chemical fertilizers.
Use Both Organic & Chemical Fertilizers
Sometimes you might want to use a combination of organic and chemical fertilizers.
For example, if you typically use organic fertilizers, but find your plants seem to be lacking in certain nutrients and are suffering.
As a result, you might give them a boost with an application of liquid fertilizer.
If you usually add organic matter to your soil, occasionally apply liquid fertilizer as a foliar fertilizer to be absorbed by the leaves.
This is a good fix for some nutritional problems.
For example, if you fertilize with compost, your plants will not get enough nitrogen.
This is because mulch and compost can take nitrogen from the soil during the process of decomposition.
In this case, give your plants a boost of nitrogen with a foliar application of liquid chemical fertilizer or with a shot of organic fish emulsion to the soil.
Fish fertilizer or fish emulsion is a great source of nitrogen and doesn’t tend to be hot, so it will not burn your plants’ roots as some chemical fertilizers might.
Fish fertilizer or fish emulsion is not a complete fertilizer, it’s a nitrogen booster.
Most products of this sort have an NPK rating quite unbalanced (e.g., 5 – 1 – 1).
Provide your plant with extra magnesium by giving it a dose of Epsom salts from time-to-time, regardless of whether you usually use organic or chemical fertilizers.
At the start of the growing season, give each of your rose bushes a half a cup of Epsom salts mixed into 3 gallons of water.
Use a combination of formulations of chemical fertilizer.
For example, liquid fertilizers are easier for younger plants to access and use.
As your plants mature, change to granular fertilizer.
Young plants will do better with liquid fertilizer throughout their first growing season and can then transition to granular fertilizer in their second year.
If you’re growing miniature or heirloom roses, liquid fertilizer is recommended throughout the life of the plant.
Have Your Soil Tested!
In addition to understanding the amounts and types of nutrients needed by roses, you must also understand the composition of your soil.
Soil naturally provides some nutrients, so you’ll need to balance your fertilizer with what’s already in the soil.
The best thing to do is to visit your County extension agent with a sample of soil and have it analyzed.
He or she can offer advice regarding the types of amendments you should add to the soil to balance it and make it ideal for roses.
Remember pH levels are quite important — Roses like a fairly neutral pH ranging from 6.0 to 6.5.
When Should You Fertilize Your Roses?
If you’re using granular fertilizer, you’ll need to fertilize once every month to six weeks throughout the plant’s growing season.
Container roses must be fertilized more often.
Use a liquid fertilizer, and follow packaging instructions very carefully.
If you’re starting with young saplings, wait until the plant is about half a foot tall and has about half a dozen leaves.
Be sure to wait until after all risk of frost has passed before you fertilize your plant.
About two months before the end of the growing season, stop fertilizing. This will help your plant prepare for the colder weather.
Your last application of fertilizer before the first frost should have very little nitrogen or none at all.
This helps strengthen the plant without encouraging leaf growth.
Use rock phosphate or bone meal for the end of season fertilizers.
Both of these help strengthen the roots and prepare the plant for optimum blooming in the growing season to come.
Water is Life!
Remember no matter how well you feed your roses, they will not be able to absorb or utilize the nutrients without water.
Be sure to water your rose bushes amply and thoroughly.
If you overfeed your roses and underwater them, the very food, you give them will burn their roots.
Remember to water fertilizer every time you apply it, begin by giving your plants a good watering with plain water, apply fertilizer, and then water again.
Consider your weather conditions when deciding exactly what sort of watering schedule you wish to keep.
If the humidity is high or the soil is extremely dry, your plants will not take up nutrients as efficiently.