Many studies have shown significant increases in yield of lychee crops as a result of honey bee pollination, including fruit set being three times greater when inflorescences were open to honey bees when compared to trees that were bagged to exclude them. Lychee yields can sometimes be unreliable, erratic and rarely approach the capacity of the tree.
Crossed fruit are generally heavier and yields in rows with two cultivars adjacent to each other have been shown to be 36 per cent higher in lychee.
All of these studies clearly show that lychee require at least one other cultivar and an abundance of insect pollinators for pollen transfer to assist with pollination by wind. Bringing in honey bee hives could be necessary to increase pollinator numbers, increase crossing between cultivars and produce a good quality yield. For this reason, it is recommended that hives per ha would be adequate for optimal pollination of lychee. Additional fact sheets and web links about the pollination of this crop are listed below.
Please be aware that some of the information was developed overseas, and environmental and seasonal variations may occur. Lychee , Purdue University, Indiana. Distribution of lychee production by state and territory —18 based on LVP. The industry overview and graphs on the value of production and crop distribution are from the National Plant Biosecurity Status Report , Plant Health Australia, Canberra.
Spotted anything unusual? BeeConnected app Pollination agreements Pollinator reliant crops Pollination and pesticides Preparing for varroa Native bees. The buds develop into a panicle during December and January. The flowers which are borne on these panicles develop from February through March. Fruit resulting from trees which flower very late in the cycle often to not fully mature. A fully developed panicle consists of a main stem or spine known as a rachis with lateral axial branche.
These branches are covered with one or more spikelets each having three small greenish yellow non-fragrant flowers approximately 2 to 3 mm in length. Lychee flowers do not have petals, but they do possess the typical anatomical components of a flower: ovary, style, stigma anthers.
An example of a flower panicle is shown in Fig. They all form on the same panicle and mature at different times over a two to six week period on most cultivars. Plants that have flowers of both sexes occurring on the same plant are referred to as heterogamous. The ratio of different flower types varies among cultivars and can affect the amount of fruit setting during a season. The three stages of development are as follows: Male flowers open and release viable pollen Hermaphrodite females flowers open which set fruit if pollinated Male hermaphrodite flowers open and shed viable pollen.
An hermaphrodite flower is one having both male and female parts in the same flower. The male and male hermaphrodite flowers produce the pollen that fertilizes the females, although the male flowers in the third stage are most responsible for fertilization as the anthers of these flowers tend to shed the most viable pollen. Julia Morton's book Fruits of Warm Climates, suggests that non-viable or damaged pollen may result in abortive seeds.
The resulting seed is small and shriveled and often referred to as a "chicken tongue seed. The pollen bearing anthers are attached to these long filaments. An example is shown in Figure 2a,b,c. When the pollen is ripe the anthers turn yellow and break open to release the pollen to fertilize the female flowers.
Each anther may produce several thousand grains of pollen. When the pollen comes into contact with the stigmatic surface of the female flower the pollen germinates and forms a tube which penetrates into the stigma and then the ovary. Lychee flowers open primarily during the daytime from 8 am to 4 pm.
You will note the two distinct atria on most of the female ovaries. The female flower also has stamen with pollen sacs that never open to release pollen and degenerate. Female flowers usually open in the earlier morning from 7 - 8 am and again in the afternoon between 2 - 5 pm. The stigmatic surfaces are stickiest and most receptive immediately after they open. Flower has probably not been pollinated Female flower diagram showing the distinctive parts: stigma, style, ovary and pollen bearing anthers Diagram Courtesy of Agrilink: Department of Primary Industries, Queensland Horticulture Institute Hermaphrodite Male Flowers: Hermaphrodite male flowers have degenerated pistils the receptive female part that has a stigmatic surface that receives pollen with undeveloped ovaries and no stigma on their styles.
These cannot form fruits. An example of this type of male flower is shown in Figure 4. You will note that the male flower to the left and right of the already fertilized female flower at the top of the photo clearly display the degenerated pistils and undeveloped ovaries.
On a single tree panicles emerge and develop at different times. Cut fertilizer back to once a month or so in the winter. Many different cultivars of lychee are used in different areas of the world.
These are the most popular cultivars in the U. Lychee trees will take at least five years to mature before bearing any fruit. You must expose the tree to cold temperatures for at least hours in the winter if you want it to bloom and then bear fruit, and the female flowers have to be pollinated. In an orchard, pollination is done by insects, but for indoor trees, you will have to hand-pollinate.
The fruits of the lychee grow in bunches. Allow them to ripen on the tree to a pink-red color. You can test one fruit in a bunch to see if it is sweet enough. Cut the entire bunch of fruit close to the branch to harvest. Lychee can be maintained as small patio trees in warmer climes or grown into or foot trees in the ground. In pots, the plants should be repotted every spring until they reach your maximum growing size.
To help keep the plant smaller, aggressively prune the main growing trunks annually to encourage a smaller, bushier plant. Lychee is typically propagated commercially by air-layering. This a sophisticated technique where growers make a cut into a thin branch and then surround it with a packet of moist moss or soil. Roots will form in the cut area, allowing the grower to cut off the whole branch and plant it as a small tree.
A home grower is more likely to start lychee from seed. To sprout seeds, cover them with potting soil , keep warm and moist, and wait for sprouts to emerge which can take weeks. Once they've sprouted, move to a sunnier spot after a few weeks. Keep a lookout for mealybugs , aphids , and mites. Signs of infestation include tiny webs on plants, clumps of white "powdery" residue, or visible insects on the plant.
A product like pyrethrum is made to control aphids and pests that flock to fruit trees. Spray it on the lychee per the product directions and it should kill the pests on contact.
Treat infestations as soon as possible to prevent them from spreading to the rest of your collection. Actively scan device characteristics for identification.
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