Rock flour: apply rock salt for roses + lawn

The Content Of The Article:

Rock flour: apply rock salt for roses + lawn: lawn

Often rock flour is brought in connection with fertilizers, which is not a fertilizer in the true sense. But it is still very valuable for your roses and the lawn, so that a regular spreading brings visible benefits. Find out more about this material and a detailed expert guide on the correct application on lawns and roses, in the following.

Product description

Rock flour is a crushed material, which is also available as this in the garden trade. It is sold as a small-grained product, which usually has a grain size of about 0.063 millimeters and thus has a floury consistency, whereupon the name is derived.
The primary rock flour does not exist as a classic fertilizer to buy, but is one of the soil additives.


Primitive minerals are usually extracted from the exits of glaciers or volcanoes. The latter consists of a particularly large number of different minerals. A special process with high energy consumption causes the breaking into small pieces of rock. The grinding then takes place in a so-called rock mill, where the final product is a fine powder and sorted out of any coarse particles by sieving.


It is usually made of basalt and / or lava stone. Diabase, quartz and zeolite and phonolite can also be considered as starting material. Rarely does granite use. Which constituents are exactly present in the rock flour depends on which starting material it is. These in turn then also influence the respective product properties and are suitable for various fields of application. Higher iron compounds can be found, for example, in lava powder than in basalt or diabase rock flour.
Mostly, however, it mostly consists of silicic acid, which usually accounts for about 80 percent of the substances contained therein. Eight to 35 percent are usually covered by alumina and other minerals and trace elements, which include iron and silica, among the most important:
  • magnesium
  • calcium
  • potassium
  • molybdenum
  • manganese
Main nutrients, on the other hand, are minimal or absent, which is why this plant compound does not fit into the range of conventional fertilizers.



While conventional fertilizers primarily act directly on the plant and provide additional nutrients, ground minerals target pure soil quality. Here they are able to improve / optimize them by enriching the soil with mineral trace elements. Depending on the starting material, it is also used to increase the nutrient storage of the earth. Ground minerals can have a higher lime content and thus neutralize acidic soils. For an application for the lawn or for roses, however, an increased calcium content is less suitable.
In humid regions of the earth, on the other hand, lava and basalt flour have a positive effect on the storage capacity of nutrients and the formation of humus. It is mainly used by hobby gardeners who fertilize ecologically with plant feces. By adding primary rock meal, the otherwise severe odor is alleviated, which is particularly advantageous in vegetable beds near homes or outdoor seating.


The effect of rock flour applied on the lawn or in the bed of roses only becomes apparent over time, when it has been used regularly over a longer period of time. Occasional application of the ground rock meal to the soil of lawn or roses will show no visible effect. When using on lawns and in beds of roses, it must be taken into account that there are sometimes different requirements. For this reason, there are special rock flour products for turf and for roses, a conventional primary rock flour plant product can be used for particularly delicate flowers. If long-term efficacy is achieved, it will end after approximately three years from the last application.
TIP: At least once a year, carry out rock flour in the bed of roses and / or the lawn. This is enough to extend the duration of effect over a whole year, if a sufficiently high dose is chosen.
The constituents of a rock flour decompose in a slow manner and are thus also slowly plant available. When lawns, the effect manifests itself in a dense and vigorous growth and a rich-green grass color. Weeds are less and less likely to spread in the grass. Iron and magnesium, for example, minimize moss growth in the lawn.
In the case of roses, the primary rock meal helps to make them more resistant and makes them more resistant to diseases. In addition, it protects roses from parasites.With an existing pest infestation it reduces the parasite activity and helps with diseases to an increased chance of the recovery. The improved soil quality stimulates growth and ideally extends the flowering period.
TIP: The finer the ground rock meal is ground, the faster an effect sets in, because the smallest particles penetrate more quickly into the ground and can therefore act faster. So always pay attention to a high degree of fineness when buying.

Dose and application

Groundbaits are usually given from spring to autumn. For continuous improvement of soil quality and mineral and trace element supply, it should be given in small quantities on the lawn and in the bed of roses every four weeks from spring onwards. The best start is before the fertilizer season, because the flour and its effect can already be used to better store the ingredients of fertilizers in the same year.
An oversupply is not to be feared. Depending on the product, the dose recommended by the manufacturer varies. At this you can orient yourself. The usual dose is calcareous soil of up to 150 grams per square meter. For acidic soils, the usual dose is usually between 200 grams and 300 grams. Heavy tasters, such as roses and turf tolerate maximum doses.

Lawn - meadow - grass

If there is an acute case of deficiency symptoms, weeds, pests or fungal diseases, the dose should be increased and the doses increased once daily. The administration must be done in combination with a lot of water, as ground minerals rely on them in their decomposition, which must be done before they can spread their effect.


When distributing primary rock flour you have a choice of roses and turf:
  • By hand, sprinkle the flour over the bed and the roses - recommended for pest infestation or for prevention
  • Mix with water and add to the soil as irrigation water. - Also suitable for spraying in case of pest infestation
  • When planting, if necessary, bring well-distributed compost into the soil
  • Distribute the flour on the soil around the rose and pour it so that it infiltrates
  • When making other organic fertilizers such as nettle, it can be added
  • Before spreading, cut and scarify the lawn
  • Evenly distribute rock meal with the hand or fertilizer cart on the lawn care
  • Then blow up the lawn - it can be dispensed with in the event of rain
  • Spread with the grass seed on the surface of the earth
  • Incorporate into the upper earth area before laying turf

to buy

There are countless different types of rock flour products available from specialist retailers. Since it is often not easy to decide for the right thing. Basically, as already mentioned above: use for your lawn only for lawns specially suitable rock flour and for roses products for sensitive plants. Mostly rose species are sensitive to lime, so you should pay attention to a low calcium content when buying. The prices can vary greatly. If necessary, a price comparison is worthwhile here, because despite possibly large price difference, the same ingredients in a similar composition can very well be present in products of different price ranges.
You can orient yourself at one euro per kilogram. The rock flour is available in 2.5, 5 and 10 kilograms of sacks / packs. Lava stone flour is usually a bit expensive. But especially for the lawn is worth the additional expenditure, as it has one of the highest iron content and is therefore ideally suited to the needs of a groomed-looking lawn.

Video Board: See What Happens When You Add Epsom Salt to Your Plants.

© 2019 All Rights Reserved. When Copying Materials - The Reverse Link Is Required | Site Map