The Biosphere Blog

I noticed random jujube trees looking a bit ‘not right’ one day in November 2022. And then almost overnight they looked even more ‘not right’ - as in looked like they were outright dying! Pathetic drooping brown leaves covering… more »

Introduction Fruit fly is an absolute scourge of a pest. If you have ever experienced just one infestation for yourself, then you will fully appreciate the devastation and its potential to literally wipe out the livelihood of commercial fruit growers… more »

Soil Organic Matter (SOM) ‘Organic’, in science, means nothing more than ‘contains carbon’. It doesn’t imply ‘healthy’ or ‘good for you’ — atrazine is as much ‘organic’ as is glucose.… more »

This post is for people with small (or no) yards, or who otherwise can’t or don’t wish to set up an outdoor compost pile, but who would still love to ‘do their bit’ and feed their trees at the same time. This composting-in-a-box… more »

Composting Composting is an age-old technique of converting waste organic matter into nutrient-rich soil amendments that add fertility to a soil. There is the slow method of ‘cold’ composting, and then there is the faster ‘hot’… more »

The other day I was chatting to a neighbour about, of all things, Casuarina sp. (’She-Oak’) and the mulch they create from all the ‘needles’ they shed. (Casuarinas seem to be a very much under-appreciated and much-maligned tree,… more »

While waiting for the terminal buds of the 2020 Ta-Jan blogging tree to do — or not! — as predicted, I thought a post on transplant shock an interesting diversion this week. Back on the 22nd September 2020 I did a photoblog post showing the two years of… more »

The Air-Pot® Having recently discussed root anatomy here and here, and this being the time of year deliveries are being prepared and people may be thinking about pots and potting, I thought I’d keep to the root theme by writing about a particular… more »

Chromium (Cr) Chromium (Cr) occurs naturally in soils from weathered rocks, but mostly as the chromium(III), or Cr3+, ion. This ion clings tightly to the negatively-charged sites of clays and organic matter, or forms insoluble compounds unavailable to… more »

I’ll open this post by briefly referring back to nickel (Ni) in last week’s post: the element that walks a tight line between being beneficial and being toxic. Nickel (Ni) sits right next to cobalt (Co) on the Periodic Table, and closely… more »

The macronutrients and micronutrients covered earlier are the main twelve essential for plant survival and growth, and the ones routinely included in complete fertilisers. A few other nutrients not often mentioned also have beneficial roles, and these… more »

Deficiency Symptoms Which Appear on Oldest Leaves First The following deficiencies appear on older leaves first as the elements involved are very mobile within a plant. If a nutrient on this list isn’t available in sufficient quantities to satisfy… more »

Availability to Plants Boron in soil ranges from 20 to 200 ppm (parts per million), but most of that is unavailable to plants. The boron that is available ranges from 0.4 to 5 ppm, and mostly as the compound boric acid, B(OH)3. Boric acid readily… more »

Fun Fact: Lead gets its chemical symbol Pb from the Latin word for lead: plumbum. Molybdenum gets its chemical symbol Mo from the Ancient Greek word for lead: molybdos (μόλυβδος) as molybdenum ores were confused for lead ores! Availability to Plants… more »

Availability to Plants Copper is found in soil at extremely small concentrations of 5 – 50 ppm (parts per million), and mostly in rock minerals. Copper, as the Cu2+ ion,  binds tightly to organic matter, more so than other micronutrient cations such as… more »