Re: mediterranean type nitrogen fixing plants

---

That's what Dr. Ingham says too.

Compost.

Cathe'

 

On 11/22/06, Tony and Moira <t*@xtra.co.nz> wrote:

 

----- Original Message -----

 

On 11/20/06, de Winnaar, Charl <d*@attglobal.net> wrote:

Hi

 

With the advent of summer some of my established plants, especially Lavender and Barleria, are showing signs of, what I believe, is nitrogen deficiency. That is, their leaves are yellowing and, although the growth doesn't seem to be affected, it is unsightly.

 

Two questions:

 

Is there any other possible explanation for the yellowing?

I am looking for a long-term low-maintenance solution. I know there are plants that fix nitrogen in the soil and my intention is to companion plant the ailing plants with these. Have any members got any suggestions for waterwise plants that could fulfil this role and would also survive acid sandy soil and hot salty winds?  

 

Charl,

I have just given an explanation to Diane Whitehead about legumes and nitrogen-fixing bacteria, but I think your probem is much more a case of aestivation (summer dormancy) which I also explained in detail to her. If your plants are in an acid sandy soil with minimum watering it is quite likely there is not in summer enough water to do more than keep them alive until the autumn rains.

 

This sort soil is also most unfriendly to any type of legume, and certainly to one with effective N-fixing nodules. The ideal for any sort of legume that is expected to fix Nitrogen is a a soil with a reasonable moisture level throughout the  season and preferably a pH close to, or above neutral.

 

Unless you can improve your soil with lots of organic matter and provide more summer water I suspect you may have to resign yourslf to some plants looking yellowish and unhappy at that time. I am pretty sure they will revive again when rain comes.

Moira