Fertilizing roses properly promotes good health and abundant bloom. Feeding roses is easy once you understand the differences between chemical rose fertilizer and organic rose food. Ways to fertilize roses.
Organic Rose Food vs Chemical Fertilizer
I have used both and I still use both as I feel that each brings something to the table that the other does not.
For instance, organic rose foods are, by nature, slow release rose fertilizers. They feed roses over a longer period.
Chemical rose bush fertilizer releases its nutrients almost immediately. Use it to fertilize your roses quickly. The drawback here is that it doesn't last long, especially in sandy soil which does not hold nutrients well.
While I do agree with the basic tenets of organic gardening, I am not fanatical about it. I find that roses planted into a bed enriched with copious amounts of high quality organic compost and then fed both chemical and organic rose food grow and bloom lushly in my sandy, infertile Florida soil.
Rose gardeners with richer soil may be able to achieve acceptable results using organic rose fertilizer exclusively.
Feeding Roses for Maximum Bloom
All chemical rose fertilizers consist of 3 basic nutrients: nitrogen, phosphorus and potassium. To these 3, some fertilizer companies will add iron and other minerals. But the basic 3 will always be included. The difference between one brand of rose food and another is mainly in the proportions.
Deciding which rose plant fertilizer to use when feeding your roses is simple once you know what each nutrient does for the bush.
Nitrogen stimulates the growth of foliage and canes. Too much nitrogen will cause the plant to put all of its energy into growing more and bigger canes and leaves to the absolute neglect of flower buds. Excess nitrogen also tends to cause excessively tender and succulent new growth that is attractive to aphids and other insect pests.
Phosphorus or phosphoric acid promotes root growth and flower production.
Potassium or potash increases vigor. Rose plants fed sufficient potash exhibit greater resistance to the major rose diseases and greater cold tolerance.
These 3 nutrients are listed on fertilizer packages like this: 18-24-16.
The first number is always nitrogen. The second is always phosphorus. The third is always potash. This never varies. You can tell at a glance what you are buying.
Here is how you use this information:
If some of your roses are getting off to a slow start in the spring, use a high nitrogen formula to jump start them into growth. Miracle Grow Rose Food is 18-24-16. Being 18% nitrogen this fertilizer promotes green growth.
Some Large Flowered roses produce weak stems which cause the heavy blooms to bow their heads in shame. A high phosphorus formula (the middle number) will promote stronger stems.
There is no single set of numbers anyone can give you which will achieve the desired effect in every case.
The important thing is to use a food which is specifically formulated for fertilizing roses. I have placed a small selection of rose fertilizers that I like right here for your convenience.
When to Fertilize Roses
These instructions apply to fertilizing roses growing in all planting zones.
Newly planted roses which have been set into properly prepared soil should not be fed until after their first flush of bloom has faded.
Feed roses which have been in the ground for more than 1 year, just as new spring growth begins. A second rose feeding should be given after the spring blooms fade and a third in midsummer.
Give each rose half a cup of granular rose fertilizer. Scratch it into the surface of the soil gently with a hoe if the soil is exposed. If your rose bed is mulched, just sprinkle the granules on top without disturbing the mulch. They will work their way into the soil the next time it rains.
If you are feeding your roses with fertilizer spikes or a water soluble rose food, follow the directions on the package. More is not better. If you increase the amount, the plants may experience fertilizer burn.
Also, always apply chemical fertilizer to moist soil. Otherwise the chemicals may burn the plants.
Fertilizing Roses in the South
In USDA zones 8-11, 1 extra feeding is necessary to encourage heavy fall flowering and get the roses through our mild winters. Give each plant half a cup of granular rose food in late summer.
Fertilizing Your Roses Via Their Leaves
This is called foliar feeding. It's a convenient way to fertilize your roses if you have a sprayer. Foliar feed when you want to boost bloom production. Do it in addition to feeding the soil, not as a substitute.
Foliar feeding works quickly because the nutrients are absorbed by the stomata (little openings) on the underside of the rose leaves.
Use a dedicated sprayer (not one which has been used to apply insecticides) and be sure to hit the undersides of the leaves.
Chapin makes a great sprayer for fertilizing roses at a low price:
Gardening and Roses
Gardening and roses is about the many ways in which rose bushes can be used around the house and yard. Pictures of roses and rose gardens illustrate gardening with roses. Gardening tips for roses.
Rose Bush Care
Carefree Delight Rose
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