What are those brown marks on my apples?

We had a great question from one of our Grow Great Fruit members recently about what causes russet on apples, which describes both the yellow marks (as you can see on the side of this Cox’s Orange Pippin apple), and the rough brown marks around the stem end of the apple.

Russet is one of those curious conditions that occurs naturally – in fact several heritage apple varieties include it in their name, like Brownlees Russet, Egremont Russet and Old Somerset Russet. It’s also commonly seen on pear varieties such as Beurre Bosc.

These days, russet is not considered an attractive trait on apples (have you even seen a russeted apple in the supermarket?), and it’s just one of the reasons many of these beautiful old varieties have gone out of favour (which is one of the reasons we’ve planted a new heritage apple orchard to preserve many of these old varieties).

Russet can also be an injury caused by environmental conditions like frost, sunburn, or hail, or by spraying your apples at the wrong time – even using sulphur (which is an organic fungicide we use occasionally) at the wrong time can cause russeting on some apples (as can a lot of the chemicals used by chemical farmers).

This damage-type russet – think of it like scar tissue – usually happens in the three weeks after petal fall, when the trees are flowering, or when the environmental challenge happens. It is often not a problem in itself, but it can make the apples much more vulnerable to other diseases, like various fungal rots, cracking, or even sunburn.

Heritage varieties that were bred in the UK, such as the divine Cox’s Orange Pippin apples (above) or the much-loved Bramley (below), are really not suited to the harsh and hot conditions in Australia, and so it’s very common to see this type of damage on your apples.

Of course once you realise that, you can set about creating micro-climates that these trees will prefer, and you may find that much of the damage is preventable.

You can find out more about creating micro-climates in your garden in Permaculture in Action.

Treasure from the storm

The concept of “no waste” is one of the permaculture principles that makes the most sense to us, because it’s how we’ve always tended to live on the farm.

It seems obvious to us (and probably to you, too), so it’s absolutely staggering that according to the “Foodwise” website, the average household rubbish bin still contains 60% organic material—40% food and 20% garden waste!

The idea of garden ‘waste’ seems decidedly odd to us, even when we get a bit more organic matter to deal with than we’re expecting.  Storms seem to be becoming more frequent, and more violent.  Last year  we had two huge storms in as many weeks – so violent they were like mini-tornadoes.

The second storm in particular brought lots of almost-ripe plums down in the orchard, and also caused a bit of hail damage in some of the fruit—again, mainly the plums. Poor plums, and poor customers, who (again) graciously tolerated a bit of hail-damaged fruit at markets. We reckon we’ve done a great job educating our customers over the years what “real” fruit looks like!

We also lost plenty of tree branches, both in the orchard and the paddocks, including this rather large branch that came down from the gum tree outside the farm shop, but luckily missed anything crucial (like the shed, or Ant’s caravan), causing only relatively minor damage to one of our beautiful tank garden beds.

Half an hour with the chainsaw and Hugh had turned it into a rather attractive garden chair that has seen the addition of a cushion and many passing bottoms ever since. Every storm has a silver lining!

Often people either don’t realise the damage they cause to the environment by putting organic matter in the garbage, or don’t know what else to do, so we’ve captured a lot of the ways that the permaculture principles can easily be put into place in a typical garden in our online short course Permaculture in Action.

Fallen branches become firewood and furniture, fallen fruit and garden waste become compost, and so the cycle goes around.

Sunburn strikes again

If you live in a hot climate (like we do) sunburn is an inevitable part of fruit growing, but it can also happen in temperate fruit growing areas during heat waves, which unfortunately are becoming more common due to climate change.

There are three types of sunburn damage you may see:

1. Sunburn necrosis


2. Sunburn browning


3. Photo-oxidative sunburn


This week Ant (who leases our orchard) had his first experience of sunburn, when the Pizzaz plums were not quite ripe enough to pick last week, then the heatwave hit—a blistering day of 44C!

You can see the spots and shrivelling on the skin – that’s a version of sunburn browning. Most of the plums are still perfectly usable for jam, or cooking, or even for eating, but it definitely downgrades them.

Is it preventable? It can be incredibly difficult in cases like this, where there was probably only a very brief window of a day or two when the plums were ripe enough to pick (with the confidence that they would continue to ripen off the tree) before the heat wave hit.

In a home garden, if you were paying careful attention to both your trees and the weather forecast, it may be possible to harvest the fruit (or at least some of it) in time. In Ant’s situation, where he’s managing the competing needs of 5,000 trees it’s much harder.

If you live in an area that experiences heatwaves there’s a number of other things you can do to prevent sunburn damage, including irrigation practices, pruning practices, and careful monitoring—we list 10 different ways to minimise sunburn in “What’s that spot? Common diseases of deciduous fruit trees” (even though sunburn is not actually a disease, but an environmental impact).

The main thing to do when a heat wave is predicted is to make sure your trees are getting enough water, which may mean watering every day. The best time to water is either overnight or in the morning, to reduce evaporation.