The mulberry tree belongs to the Morus genus that consists of about 12 species found over Mediterranean and north temperate regions with two being native to North America. The commonly cultivated black mulberry comes from an ancient line which has now been introduced into many countries of the world. It is believed to have been in cultivation for over 5000 years. It has variable leaf forms.
It produces a delicious fruit which is plentiful in summer and that ripens over a period long enough to enjoy the harvest for some weeks as the green berries mature to red or black. It is a notoriously difficult fruit to harvest, as are all the soft berry fruits, so there is ample scope for an enterprising soul to consider a way of developing an easier and efficient harvest and offering a new commercial crop.
In home gardens mulberry picking is enjoyed by children who are capable of exploring to seek to enjoy the sweet rewards as well as picking an amount for common consumption. However, they should be tutored to use the green, inedible fruit to rub away the persistent stains from the ripe fruit.
The White Mulberry, Morus alba is known as Sang Ye in China where it originated. It was introduced into Europe about 1434 from the Levant where it was cultivated mainly for the purpose of providing food for silkworms. It was introduced and is now naturalised in the U.S. providing an important food for wildlife. In Australian gardens it is welcome as a tasty home fruit, sweet and marketable also. The leaves when fed to silkworms produce a light yellow silk.
The tender young leaves are edible in small quantities when fresh or can be cooked as spinach. The leaves are used medicinally for treatment of fever and externally for ringworm. The root skin provides a medicine for bronchitis. The fruits which vary from pink to deep red/black are delicious to eat and in China it is regularly recommended to relieve insomnia, flu, high blood pressure, vertigo and other complaints. Fruit contains vitamins a B1, B2 and C.
Texas Mulberry or Morus microphylla grows as a small tree in the canyons of Texas, New Mexico and Arizona where it was once cultivated by Indians of the area and it is still considered a food source.
White Mulberry is a native of France Morus multicaulis
Black Mulberry, English Mulberry Morus nigra originated in Iran and known in antiquity when it was apparently much appreciated for its large, sweet juicy fruit. This is the species preferred by consumers large succulent fruits are delicious and sweeter, more flavoursome than the white mulberry. The unripe fruit when crushed, removes the stains from the ripe and often messy fruit. The leaves produce a lovely golden silk thread when fed to silkworms.
Red Mulberry, Morus rubra is a native of Nth America found from Vermont to Sth Dakota and south to Florida. Finely toothed leaves are coated with soft down in autumn. Red fruits are of inferior quality.
The Black Mulberry Morus nigra is often known as the English Mulberry for the following reason. In England James I tried to introduce a new silk industry into England. He issued a Royal edict recommending the cultivation of silkworms and urging the Shires to buy and distribute 10,000 mulberry plants of Morus nigra to all who would sow them, only to be advised that it was the wrong species of mulberry and the enterprise was abandoned. That is the reason that there are many ancient Black Mulberry trees still existing in England and very few old White ones. Regrettably, it was later discovered that both species of mulberry were used in the orient for silk.
Shakespeare's mentions a mulberry - a Black Mulberry - and that it was not suitable for rearing silkworms, so reflecting the general disappointment of the times.
There is one surviving Mulberry tree in the private grounds of Buckingham Palace to this day. It still is bearing but in no way remarkable in size or spread.
Mulberry leaf is an old cottage remedy for ringworm. A very important purpose of the fruit is as a food supplement in the diet of heart patients, with some remarkable beneficial results.
For those who wish to introduce the Australian home hobby for children by keeping a few silkworms it can offer a fascinating and interesting experience for both infants and parents. Unfortunately there is little ultimate pleasure to be had from the silk produced, but it is certainly an exercise in nature studies!
It would be best to be sure of adequate supply of leaves by having planted your own trees in the yard, or at least enquire about a reliable and close alternative source. The leaves are best when fresh but keep for a little time in the fridge. It may be interesting for those unfamiliar with silkworm culture to know that if mulberry leaves for any reason are not available, a temporary diet of beetroot leaves will produce pink tinted silk and lettuce leaves will tend to give lemon coloured thread.