As I walked through the car park at the garden centre I was hit by a delicious perfume. I inhaled deeply and recognised the smell of approaching autumn - the berries of myrtus ugni, commonly known as New Zealand cranberry or Chilean guava.
Chilean guava is the usual name for the bush, given that the plant originates from Chile where its fruit is grown commercially for export to Japan. The other common name of New Zealand cranberry is often a source of confusion because apart from the look of the fruit, the plant's growth and fruit taste are nothing like the 'real' cranberry.
The Chilean guava produces attractive white flowers during spring and then forms round red berries (0.5-1.5cm across) during the summer months. Towards late February and during March these berries will start to ripen. It is the ripening berries that produce the delicious smell. They are delicious to eat fresh as well as being suitable for making juices, jams and other preserves.
The plants yield quite well with a three year old plant producing approximately 1kg of fruit which will increase by about 1kg a year subsequently.
The plant themselves have a number of landscaping uses. If left unchecked they will grow to 1.5mx1m. They are best trimmed each year after fruiting to maintain some form otherwise they can become a rather straggly and leggy bush.
They are great grown in a courtyard where the scent of fruiting coincides with barbecue season. The plants can be kept trimmed to size as space allows, pruning after fruiting each year. They are suitable for containers and patio situations where their drought-hardy tendencies can be useful, although lack of water can affect fruit quality.
The Chilean guava is regularly grown as topiary. Its dense forming habit and small leaves make it an ideal candidate to offer not just good form but the added value of scent and fruit.
They also make a marvellous fruiting hedge. Their leaves resemble those of buxus but are slightly more rounded, and their dense growing habit right from the base of the plant makes the guava worth considering as a hedge. The growth habit is much faster than buxus, allowing establishment of a 30cm high hedge in two years or less rather than 3-4 years. The trade off for a fast-growing hedge is that it will need trimming 2-3 times a year to maintain a tidy look.
Culturally, they are an easy care plant with little major pest and disease risks. The main insect offender to be aware of are thrips, these will often attack plants that become stressed from drought, but are all easily controlled with an insecticide such as Yates Confidor if it becomes a problem. They are hardy to around -6C and are happy growing in full sun or part shade. They are tolerant of salty air but perform far better if they are out of the prevailing wind in a slightly more sheltered situation. They grow best in fertile well-drained soil, however being very versatile they will also grow well in clay and even in sandy soils.
Pest Watch
With prolonged warm weather there has been an explosion in insect numbers: whitefly, aphids, scale and caterpillars on many plants. The rain last week created more humidity which is now showing up cases of blight, mildew and other fungus infections as well.
What to look for now - maintain vigilant monitoring on crops for whitefly and caterpillar damage on tomatoes and cucurbits - it is wise to spray at first sign to keep the population down for as long as possible. (Population can build rapidly and once in large numbers control is virtually impossible). Mavrik is a good control - concentrate on the new growth where the pest is worst. Spraying with Watkins Fungus & Mildew Spray is recommended to control powdery mildew on cucurbits and to protect tomatoes from blight.
Another prevalent pest at this time of year is passion vine hopper, which attacks a wide range of plants. Insect sprays Mavrik and Pyrethrum will control this.
Citrus
It has been a good season for growth and fruit development on citrus but be aware, I have recently seen a lot of citrus covered in sooty mould and closer inspection shows the cause - a heavy infestation of scale on the undersides of leaves. Now is the time to apply a spray of Yates Confidor to clean up and to protect the new season's growth. A follow up spray later in March would be advisable.
Now is also a good time to fertilise citrus and ensure they are being watered deeply. The plants will have fruit formed on them now and if they become stressed due to drought, fruit may drop or quality can deteriorate. If your citrus are growing in pots or containers then ensure you use a specialist citrus fertiliser that is suitable, such as Osmocote Citrus Fertiliser. The addition of Saturaid re-wetting granules to citrus growing in containers is highly recommended.
This product should be applied annually, it channels water to the root zone where it is needed most and promotes even water distribution so there is less water run off and dry spots in potting mix and soils. It makes watering, rainfall and fertilisers more effective. It can also be used in the garden even in sandy, clay or compacted soils.