Different types of houseplants growing indoors need
different feeds and fertilizers
Houseplants that are grown for
their flowers, need a different type of Fertilizer than
houseplants that are grown for their foliage effect.
Houseplant fertilizers for feeding plants indoors are many and
varied. They all contain the main ingredients of N-P-K.
N=Nitrogen P=Phosphorus and K=Potash. Some plant feeds also
contain other elements of food - Trace elements. We will not
deal with those here.
All plant feeds should have
the symbols NPK with their percentage rate on the packet or
container. The higher the % rate the more of that particular
feed element there will be in the houseplant fertilizer.
Nitrogen, is generally needed for good healthy foliage, Phosphorus is needed
by houseplants for growth of healthy roots and flowers, and Potash is
generally for the overall wellbeing of the plant - healthy, sturdy stems and
Houseplants need feeding quite soon
after feeding, for the feed in most composts will be exhausted after
just a few weeks. (This is also true of general composts!). With plants
grown indoors, there is a regular watering regime, which aids the loss
of nutrients from the root zone, and also bear in mind that the compost
is not replenished with re-cycled food - such as dying organic matter -
as normal soils are in the outdoor environment. We have to provide the
Feed for the indoor plants.
High Nitrogen feeds are often
recommended for foliage houseplants. In an indoor artificial growing
environment, this can lead to overly lush growth, which in turn leaves
the plant susceptible to a wide range of fungal diseases - botrytis
being among them.
Bearing in mind that most houseplants
will have very little of any of the mentioned elements - NPK - of
substance in their pot soil after a month or so, it is normally quite
alright to go for just a general liquid feed. No need for high Nitrogen
or Phosphorus in most cases. A general houseplant liquid fertilizer will
do the trick for most plants. Another favoured alternative, is to use a
weak solution of a Tomato feed. This will typically have a ratio of
7-7-7 NPK or similar, together with which most will also have traces of
other elements such as Magnesium. The great thing about Tomato feed for
houseplants, is the fact that tomato feeds have been formulated for use
in composts (Growbags etc. ) where the growing requirements are very
similar to houseplants in compost!
Little and often through the
Don't feed any houseplant in the
Do NOT feed a houseplant compost
when it is dry. Make sure that the compost is at least moist - or
the plant will fold and die!
Use half recommended dose of
Tomato feed for all houseplants.
Start feeding gently at first sign
of spring - March/April and continue through season - probably best
at fortnightly intervals.
Your houseplant will grow well, so
may need re-potting during the season.
An alternative to liquid houseplant
feed, is either plant sticks - which are simply pushed into the pot
around the edges - or Osmocote, which is a granular fertilizer which can
either be incorporated into new potting soil, or can be bought as
'single plant' dose capsules to be pushed down into the soil. The great
thing about Osmocote, is that it will feed the plant for the whole
growing season. best incorporated in early spring.
By David Hughes -