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The Best Way To Fertilize Rose Bushes – How To Get Your Rose Bushes To Bloom Big!

Fertilizing your rose bushes at the right time and with the right fertilizer can help you grow healthier, disease-free bushes. And even better, more roses that can be bigger, brighter, and more vibrant as well!

Roses are heavy feeders from the soil. Not just when they are blooming and producing their incredible flowers, but also as they leaf out and produce new shoots and stems in the early spring.

Unfortunately, when a rose bush runs out of power from the soil, it doesn’t just mean fewer blooms and flowers. A lack of available nutrients for a rose bush can also spell trouble for the plant’s health and well being.

fertilizing rose bushes in the spring
Providing a steady supply of power to your rose bushes throughout the growing season can produce bigger blooms that are full of vibrant color.

When a rose bush fails to get the get the food it needs for proper growth, it creates a plant with less resistance to disease and pests. In addition, the bush’s root structure can become weak and unstable as well.

All of those issues can lead to a weak and feeble plant. It can also make the rose bush vulnerable to freezing out over winter. But that is exactly where fertilizing your rose bush properly can help save the day!

With that in mind, today’s article is all about when and how to fertilize you rose bush for optimum health. And, of course, to also help it produce the biggest, most beautiful blooms around!

Giving Roses The Nutrients They Need – How To Fertilize Rose Bushes

To reach their full potential, roses need a fair amount of nutrients from the soil in which they grow. In addition to the usual plant needs of Nitrogen, Phosphorus and Potassium (N-P-K), roses also require small doses of calcium, sulfur, copper, manganese and a host of other micro nutrients.

How much additional power a rose bush will need depends on the type of rose you are growing. For instance, Grandiflora and miniature roses require more constant feeding. As do tea rose varieties that use the added nutrients to continue producing new blooms.

fertilizing rose bushes
Shrub roses do not require as many nutrients to produce their flowers as other rose varieties. Because of this, a spring and mid season application is more than enough to power them through the season.

In addition, roses growing in pots or in confined spaces will also need to be fed more often as well. However, with more stable climbing and shrub roses, the need for constant feeding is not as vital. These roses still need fed for sure, but just not as often.

We will cover more on when and how to feed roses later in the article, but let’s first look at the best fertilizers to use when it comes to powering any and all of your rose bushes.

The Best Fertilizers For Roses

Although there are a wide range of man-made fertilizers for roses on the market, you can quite successfully employ an all-organic approach for both slow release fertilizing, or a quick boost of in season liquid fertilizing. Not only can they be quite effective, the can be far less expensive too!

Slow Release Fertilizing

When it comes to staying all-natural for slow release fertilizing, two of the best to use for roses are worm castings and compost. When used together, they can provide a steady supply of readily available power. Power that can keep them healthy and blooming strong all season long.

Worm castings, when applied to the soil around rose bushes, work as the perfect slow release fertilizer. Working in a 1/2 cup to a full cup of castings in the soil early in the season will provide plenty of steady power. Product Link: Worm Castings

how to use worm castings
Worm castings are filled with a balanced blend of nutrients that are easily absorbed by roses.

Because castings can be slightly alkaline (roses prefer slightly acidic soil), applying a few cups of compost to the base of plants when feeding with castings can help to counterbalance and keep your roses thriving.

Compost, just like worm castings, is 100 percent organic. Just as with castings, its nutrients are easy for roses to absorb as well. Together the two can provide all your roses need for slow release nutrients.

There are also a whole line of organic rose fertilizers that are wonderful for this type of fertilizing as well. Some, such as Burpee Rose + Bloom Organics, contain a full compliment of nutrients for feeding up to 3 months.

Liquid Fertilizers

Liquid fertilizing is the perfect compliment to slow release fertilizing. It can be used when you need to give your roses a blooming boost in season.

Once again, compost and worm castings can do the job quite effectively and naturally. A powerful fertilizing tea can be created from either compost or worm castings for a more immediate source of nutrients.

When applied, the tea is absorbed through the roots and leaves of roses. Although both work well, worm casting tea is even thought to help with disease resistance for issues such as black spot. (See: How To Use Worm Castings)

If you are not into making your own teas with compost or worm castings, you can also purchase all-natural fertilizer options. One of our favorites is Jobes Organics Rose & Flower Fertilizer. It’s formula is certified organic, and can be a great alternative to compost and castings.

Check out our podcast on Compost Tea below!

When To Fertilize Your Rose Bushes

Shrubs and Climbing Roses

Now that we have covered what you can fertilize your roses with, it’s time to cover when to fertilize them. Again, how often you will need to fertilize will depend on the type of roses you grow.

For more hardy and established shrub and climbing roses, two applications of fertilizer are usually more than enough to power the plants.

With these applications, mixing 1 cup or castings and 3 to 4 cups of compost and mixing them into the soil around your rose bushes works wonders.

For these rose bush types, fertilize once in the early spring as the plant begins to leaf out. Then, as the first blooms begin to appear, fertilize once more to help provide blooming nutrients. These types of roses do not require liquid fertilizers to keep performing at their best.

Tea Roses & Standard Roses

For tea and other standard rose bushes, a bit more frequent fertilizing during the season can help the bushes for more prolific blooming.

fertilizing a tea rose
Tea roses require a more constant supply of nutrients to produce strong blooms. Fertilizing not only improves the frequency of blooms, but their intensity as well.

Just as with shrub and climbing roses, an early spring application will help produce strong foliage. Using the same ratio ( 1 cup castings / 3 to 4 cups compost) will work. After the initial feeding, applying additional applications of liquid fertilizer every 3 to 4 weeks during the growing season can really power blooms.

If you happen to be growing your roses in a confined space such as a container or pot, apply every two to three weeks to keep the soil productive. By their very nature, potted plants simply run out of nutrients at a more rapid pace.

This is where the liquid compost or worm casting tea can be extremely effective in helping roses to deliver strong and vibrant blooms.

When using any liquid fertilizer, always apply in the early morning or evening. At these times, the sun’s rays are less intense and will not burn the foliage as it is watered.

How To Fertilize Rose Bushes

When To Stop Fertilizing Rose Bushes

One of the biggest mistakes gardeners make with roses is to fertilize them too late in the growing season. Giving any type of rose bush additional nutrients in late summer or early fall can actually harm plants way more than help them.

All fertilizing should cease around eight weeks prior to the average first frost date in your area. Fertilizing after this point will cause your bushes to produce tender new growth too late in the year.

Unfortunately, that new growth is extremely vulnerable to damage from harsh winter conditions. Even more, the resources the plant uses to produce the growth can take energy from the roots. Unfortunately, this can leave the entire rose bush in jeopardy of freezing out during a rough winter, or with less nutrients for blooms next year.

Know Your Soil’s PH Level

One final note on roses and fertilizing. It is important to understand that in addition to having plenty of nutrients in the soil, rose bushes prefer growing in soil that is slightly acidic.

If you are fertilizing your bushes properly and still having blooming issues, it is a good time to check your soil’s PH. In general, rose bushes prefer to grow in soil with a PH of 6 to 6.5.

You can use a hand held PH meter to quickly test your soil’s PH. If it is too acidic, you can add lime to raise the PH. If it is on the alkaline side, you can add an acid enhancer or sulfur to lower it. Here is to growing bigger and better roses this year!

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