Local gardeners, particularly those growing roses, may have noticed unusual, circular shapes appearing on the leaves of some varieties.
Subscribe now for unlimited access.
$0/
(min cost $0)
or signup to continue reading
A search for caterpillars or something else responsible will probably prove fruitless as the shapes are actually caused by the leafcutter bee, a species different from the well-known honey bee. Gingers and roses are common plants targeted but they use a wide range of leaves. Leafcutter Bees are mainly black with white hairs.
The presence of leafcutter bees is usually indicated by their distinctive leaf damage. Females cut interesting oval and circular pieces from soft leaves. They use their strong mandibles to cut the shapes. The leaf material is then used to make cells in their nests.
Nests are usually built in existing crevices such as window frames or hollow twigs and stems. Eggs are then laid in the newly created cells. A few species burrow in the soil. The cell walls are made of overlapping oval leaf pieces and capped with circular pieces. Cells are placed one in front of other until the cavity is filled. Each cell is filled with pollen for the growing larva. Cells are built in a row from the back of the hole to the front.
Although the bees cause disfiguration of the leaves, no long-term damage appears to be done to the plant.
In fact, the bees assist in the pollination of plants, so their presence in the garden is very beneficial. Large amounts of pollen are attached to hairs on the underside of the bees.
Gardeners may be encouraged to provide nesting places for the bees in their garden. A simple nest can be made by drilling some small holes in a wooden block or log. Placing the log where it has some overhead protection from rain would be beneficial. The 'house' can be hung or placed in a sunny or partially sunny part of the garden.
If holes of differing sizes are drilled, other small, beneficial insects may also be encouraged to use the wood for the nest.
BULB TIME
One of the interesting things that happens in many gardens at this time of the year is the sudden appearance of bulbs in the Amaryllis family. Two main groups of bulbs in this family are evident now.
Spider lilies, Lycoris, produce exotic flowers with ruffled petals in colours of yellow or red. They feature long stamens and are produced on thick stems 40-60cm tall. Lycoris originate from China and Japan, with flowers resembling Nerines.
Lycoris aurea produces beautiful golden flowers, while lycoris radiata have flowers in a pink/red colouring.
The other members are the Belladonnas, also known as 'Naked Ladies' because of the appearance of the flowers before the leaves.
RELATED CONTENT: Secret of healthy citrus
These flowers originate from South Africa. Flowers are produced from large bulbs with a strong stem up to 75cm in height.
Clusters of flowers are produced, predominately in shades of pink, although white varieties are also available.
Stems suddenly appear as they push through the soil surface and then they quickly reach their mature height, with flowers being produced. The whole process can take less than a week.
Foliage appears after the flowers.
Bulbs can be grown successfully in pots or containers, as well as the general garden. They grow well in positions of full sun, as well as areas of semi-shade with morning sun. Soil should be well-drained and fertile.
The bulbs should be planted at a depth that will allow the top to be just above the surface of the soil.
Bulbs can be fertilized when the strap-like leaves finally appear. The leaves should be left until they have fully died down as it is during this period that they feed.
Bulbs are tolerant of being left in the garden without attention. They are often seen flowering in seemingly abandoned country gardens. They prefer a sunny position.
They flower more prolifically when they have been left undisturbed for several years, forming clumps.
However, overcrowded clumps may be divided in late spring or summer. The bulbs will often not produce flowers in the season following division.