Since i first took my plot in 1979 every feb i have top dressed the plot with
1 part potash
3 parts phosphate mixture
3 weeks before planting
Good for root growth, or so i am told, but is it?,has any one else done or doing the same thing.
I'm not that scientific: I just usually use dung!! :o :o ;D
A soil test is the best way to find out what amendments are actually necessary.
http://www.rhs.org.uk/Gardening/Help-advice/RHS-Advisory-Service/RHS-Soil-Analysis-Service
we were advised by Eric(60 years gardening) to use blood, fish and bone on our brassicas, never had much luck with them, this year, best year ever, apart from swede so that's next year's target, grow some decent swede ;D
Plants require the various plant foods (fertilizers) in different amounts. There are three major plant foods which they require in fairly large amounts.
These are nitrogen (N) phoshate (P) and potash (K) then there are minor plant foods which they need in smaller amounts. These are calcium, sulphur and magnesium.
There are also trace elements which are only required in minute amounts. These are iron, baron, maganese, molybenum and copper.
most soils contain adiquate amounts of all these plant foods except the major ones. When we add fertilizers to the soil the purpose is mainly to supply one or more of these major plant foods.
To simplify the functions of these makor plant foods:-
NITROGEN (N) is the element mainly responsible for growth of srems and leaves rather than flower or fruits. Leafy vegetables such as cabbage require a high proportion of nitrogen
PHOSPHATE (P) has more than one function but its main one is for root growth. Plants need it right at the begining for the germination of the seeds andto form a good root system.
POTASH (K) is for good flower and fruit production and is required in large proportions by plants such as tomatoes.
During the winter months you should take a soil test so you know which fertilizer to apply a few weeks before planting. The idea is to see that each bed contains adequate but not exessive amounts of the three plant foods
Nitrogen tends to leach out of the soil with the winter rains, but the other two build up if ferilizers containing them are added in excess. An excess does more harm than good because the minor trace ellements can be " locked up " and not availible to the plants.
If you don,t want to go to the trouble of doing a soil test then you cannot go far wrong by adding fish, blood and bone at three or four onces per square yard.
Once the plants are growing i then go over to liquid feeds, different ones for different crops as and when i think they may need it.
thanks davey
after planting and sowing i use grow more and change to a liquied feed later on, no complaints so fare.BTW what do you recomend for liqu feed, i use phostrogen.
jim