Dear all.
There is a lot of benefit from fertiwatering, that is using a very dilute solution of a suitable fertilizer in every watering. The problem is that using a complete fertilizer is not any solution. Australian and South African natives live naturally in poor soils and any excess of feeding is poisonous to them. Nitrogen in particular is dangerous as it produces soft tissues very susceptible to rots by fungi and bacteria and that attract sucking insects like aphids.. It is a lot better to use vegetal organic matter as the only source of nitrogen; it will decompose slowly and the plants will take it gradually.
Many bulbous plants find phosphorus poisonous. Another reason not to use complete fertilizers in all kinds of bulbs.
The nutrient that bulbs must have at their disposal during their vegetation (foliage) period is potassium, particularly in the period between flowering and when the foliage is withering as the plants enter dormancy.
In Holland apparently a lot of fertilizer is used but this is not true as there is a lot of leaching because of the sandy porous soil. Heavy fertilizing is the safest way to get rid of your bulbs/plants of any kind.
Regards
Alberto (Castillo), Argentina
From ???@??? Tues Aug 27 11:03:28 2002
Subject: Fertilizers
From: "Mary Sue Ittner <msittner@mcn.org>" <msittner@mcn.org>>
Date: Tues, 27 Aug 2002 23:47:41 +0000
To: <pacificbulbsociety@lists.mcn.org>
Dear All,
My IBSA (Indigeneous Bulb Growers of South Africa) bulb chat has just arrived. I really do fine it informative. They have been sending it monthly along with a report from their meetings that includes a list of all the plants in bloom displayed at their meetings. This month there was an item relevant to this thread which I will share. It was entitled: Feeding: tips from a successful grower.
"Many of us have experimented for years with various feeding regimes. One of our successful growers has noted that despite feeding his Lachenalias with Potasium Sulphate the leaves do not look too happy. The leaves seem to be brittle and break easily. He had previously fed his Lachenalias with 3:1:6 with great success. This year he is not happy with the condition of the Lachenalias. Feeding the Iridaceae with Potassium Sulphate at 5 ml to 5 liters of water seems to do the trick. The leaves are greener than usual and the plants are more robust. Those brown leaf tips are a thing of the past. It might be a good idea to alternate the feeding of Iridaceae between 3:1:6 and Potassium Sulphate. The Potassium Sulphate will also lead to bigger corms at the end of the growing season."
My friend Bob Werra who grows Calochortus told me recently that he tried fertilizing his plants last year and was not at all happy with the results. So next year he is not going to do it.
Alberto, what do you mean by vegetal organic matter?
Mary Sue
From ???@??? Tues Aug 27 11:03:28 2002
Subject: Fertilizers
From: "Alberto Castillo" <ezeizabotgard@hotmail.com>
Date: Tues, 27 Aug 2002 23:47:41 +0000
To: <pacificbulbsociety@lists.mcn.org>
Dear Mary Sue et al:
Organic matter for bulbs must be of vegetal origin (say decomposed leafmould) and never of animal origin (like manure) as plant debris decomposition is slow and would not produce a raise in temperature (necessary for harmful fungi and bacteria proliferation). In other words it is a "cold " decomposition.
The dose for sulphate of potash mentioned (5 ml/5 litres) is not clear as it is a salt, a solid, measured in grams, ounces, etc. If you say 5 ml you mean the solid has been dissolved in a liquid (normally water). We need to know how much solid sulphate of potassium was diluted in water in those 5 ml for the information to be of any relevance.
Leaf tips burn indicate root scorching by high doses or improper fertilizer application.
Potassium beneficial effects are normally not very apparent when it is been used on the plants. But the NEXT season of growth the plants are a lot more robust, bigger and healthier. It is effective to speed maturation (those plants never reaching flowering size!) and increases the plants' resistance to frost. The bulbs and corms fed with potassium do not grow bigger tho. It is not the size but the quality of the stored materials what is noticeable.
Bob Werra is a most serious grower of Calochorti and Moraeas, it would be of interest to know of his fertilizing results.
The most successful grower of Hipeastrums ever, the great Len Doran, used a fertiwatering regime on his plants and many of them had leaves 1 metre long and his seedlings would flower in their second year. His findings were generously shared in a back issue of Plant
Life (1976?). They were the result of scientific research. The doses were so minute that they were the equivalent of the plants being grown in a naturally very rich soil
Regards
Alberto