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UNRIPE APPLES
Is it possible to ripen apples off the tree? I took quite a few off my overloaded tree. The apples were partially red when picked but should be fully red when ripe. ROBERT SKINNER, NORTHLAND Unripe apples do mature a bit more after picking but they won’t taste the same as those that have ripened on the tree. The texture can differ too – like some supermarket apples that go soft and mealy after a spell in a cool store. Apples give off ethylene, the gas used to ripen bananas and other fruit. Ethylene changes starch in the fruit into simple sugars. A stored apple will get sweeter but also softer with age. It does not “ripen” in the sense that it develops any more flavour, aroma or nutrients. Depending on the variety and how mature they are you’ve got a few options. Try tasting one. You might find that it’s pretty tart but still edible raw – perhaps grated into a coleslaw or an Asian-inspired salad.
Unripe apples can be cooked as stewed apples or used in crumbles, pies and cakes. Just tweak the amount of sugar if necessary. You can make cider and cider vinegar with unripe apples too.
If you do want to use natural ethylene to sweeten the apples store them in a paper bag or a cardboard box in a cool, dark place. Place in a single layer or wrap in tissue or newspaper so the apples don’t touch. Don’t store any that are damaged or bruised. Check regularly – that saying about one rotten apple spoiling the barrel is true!
EARLY FRUIT DROP
The fruit are dropping off my columnar apple trees. They are nearly full size but not yet ripe. Is it possible that if all the fruit is growing too close together they can push other fruit off the tree? Do I need to thin the fruit earlier in the season? Or is it something else? FLEUR HARDMAN, MASTERTON The fruit on the columnar apple trees in the Ballerina series can usually handle being in very close quarters and it’s most likely that wind is knocking the fruit off.
However, it’s a good idea to consider the other common causes of tree stress, which can result in early fruit drop.
Too much or too little water; extreme temperatures, both too hot or too cold; nutrition issues; or pest and disease problems are all factors to consider.
Your trees are watered every two days on timer for an hour. Check how much water is being applied to the tree by putting a bucket under the dripper for the irrigation period. This will make sure it’s working, and is providing sufficient water. A tree of this size would probably need 10 litres of water a week.
The grass growing right up to the base of the trees will be drawing away the moisture in the surface of the soil. While there will only be a small number of roots in this shallow area, it would be best to apply mulch in a doughnut shape around the tree as wide as the widest part of the tree.
Feed it well by applying a general fruit tree fertiliser such as Tui Fruit Food, Yates Acticote or Dynamic Lifter Plus – Fruit Food. Kate Marshall, Waimea Nurseries
DEAD WISTERIA
Our beautiful ‘White Silk’ wisteria looks dead. It’s virtually impossible to kill wisteria when one wants to, so any ideas as to what could have happened? KAREN BARRETT, PIOPIO Your weeding around the roots and light pruning are unlikely to have caused this degree of damage. Assuming you can discount the possibility of accidental spray drift, then the most likely suspects are either one of the many soil and waterborne phythoptera pathogens or the lemon tree borer.
This insect is on the wing and laying eggs in fresh cuts on many ornamental and native trees and shrubs between October and March. The larvae then proceed to eat the woody branches from the inside out, destroying the plant’s ability to transport water and nutrients throughout the growing stems.
Watch for the tell-tale sawdust or frass beneath an affected branch, which indicates the presence of the borer larva within. Treat with a borer spray or run a fine wire up the stem and skewer the culprit.
As you say wisterias are hard to kill and hopefully yours will come away again from the base given some TLC in the form of food and water.
It’s also a good idea to limit any pruning of hard branches to winter to avoid the borer’s active time over spring and summer.
Good luck. Kerry Carman
POTATO ORCHID
This strange flower popped up under a tree where nothing’s been planted before. There is no leaf growth and a very woody looking stalk. Should I leave it be or root it out? JAN LOWREY, SOUTHLAND It is a native orchid, a member of the gastrodia family. This particular one hasn’t been formally named, according to the NZ Native Orchid Society website, and has been dubbed “longcolumn” in the meantime. These orchids don’t have leaves so can’t make food from photosynthesis (the sun) and instead use fungi to provide nutrients and sugars. (The fungi in turn obtain their nutrition from tree and plant roots).
Commonly called potato orchids they form starchy underground tubers regarded as delicacies by Maori who roasted them in embers or steamed them in a hangi.
The blackish-brown to pale brown streaked or spotted stems are 5-10mm in diameter and up to 1m tall.
Up to 60 knobbly flowers per stem bloom from December to January. Flowers in deep shade are often darker than those in well-lit spots.
They are usually found beneath beech, kanuka or rhododendrons in forests or scrub.
Don’t root it out. Longcolumn isn’t an endangered native species but it’s certainly special. Sandra Simpson