1. Size of the fruits and colour of the rind are not good indicators.
2. Fruits are ready for harvest in 90 to 120 days from sowing.
3. Four criteria are commonly used in determining the maturity of the fruits:
a) Withering of tendril: The tendril accompanying the fruit withers as fruit ripeness.
b) Thumping: Ripe fruits when thumped with finger give out heavy dull sound, whereas the immature fruits give metallic sound.
c) The portion of fruit, which rests on the ground, turned yellowing at maturity.
d) Ripe fruits produce a crisp, cracking noise on being pressed with the flat of the hand.
Harvesting of Water Melon:
The well mature fruits are harvested manually with the help of sharp knife or by twisting.
Maturity Signs of Muskmelon:
1. Fruits will be ready for picking in about 110 days depending upon variety. There are two groups of cultivars which behave distinctly. In one group, the fruits when mature slips out easily from the vine with little pressure or jerk or if not it will remain separated from the vine next day. This is called full slip stage. In some Indian cultivars, green stripes on the skin begin to turn yellow during maturity.
Harvesting of Muskmelon:
Muskmelon is a climacteric fruit which ripens during transit and storage and hence, it is harvested before it is fully ripe.