He is crowned with many thorns.

Our Lord was mocked during His Passion. While He is the King of Kings and Lord of Lords, He was given a crown of made thorns to be mocked and treated with contempt. He was charged with being the King of the Jews, a title the Pharisees ultimately did not want bestowed upon Christ, and one they begged Pontius Pilate to remove from the top of Jesus' cross. They asked Pilate to change the words to "He said that He was the King of the Jews", but Pilate said: "I have written, what I have written." a semi-polite way of saying "go away". Written on the plaque at the top of every Crucifix, you would see the four letters INRI. Iesus Nazarenus, Rex Iudaeorum. The charges for which He was put to death for. In reality, it just made who He is, a King. As such leading up to His crucifixion the Romans treated Him as they would treat someone accused of being a King in opposition to Cæsar, they crowned and did homage in mockery.

The Romans plaited a crown of thorns which, thanks be to God, still exists to this day. They made a crown of thorns from a plant that was introduced centuries prior during either the Greek conquests or the early Roman conquests, but was used in other forms of torture by the romans to do the thorns and types of toxicity found in the plant. The thorns of the plant are dense and woody, i.e., stiff and stabby, and the sap that oozes from the freshly harvested plant causes skin and eye irritation, and since Christ's Most Precious Blood was coming down from His head at this time His own blood would have carried it down to his eyes and surrounding skin. Not to mention that His Blood would have carried the toxins (phorbol esters) through His Body and caused other irritations and pains there. Which according to pharmacological studies * can cause lesions in lungs, kidneys, and hæmorages in the lungs as well. If the toxin is potent enough (this can depend on the amount of toxin present in the blood, which severe blood loss will lead to higher concentrations) the esters can cause cardiac muscle tissue to abruptly tear and rupture. 

So, after the Romans scourged Him, causing massive blood loss, they plaited a toxic plant and put it onto His head, and then struck the crown into His skin with a reed that was also used to represent a scepter, a symbol of royalty. They placed on Him a robe of Purple or Scarlet, both colors used for royalty as St. Augustine explains here in St. Thomas Aquinas' Catena Aurea, Vol. 2. The Romans then kneeled before Him and mockingly said "Hail, King of the Jews" and then struck Him and removed the garments and the "scepter" an act of refuting someone's royal authority, and a means of usurping the king. The crown of thorns He received is resemblant of the crown of martyrdom the martyrs receive in their act of dying for Christ. A reward for their courage in standing for Christ in this world, and the world killed them for their faith in Christ. 

The fruit for this mystery is: Moral Courage. Christ was berated, mocked, beaten, tortured, and accused of something that required Him to be put to death (since He knew the Jews would not listen to Him). Christ knowing that He was right, and their charges of Him being the Messiah and the King of Kings and Lord of Lords was true, He did not refute any of the charges nor did He defend Himself when accused. Like the Saints, Apostles, and Martyrs, they upheld the Risen Christ, and His divinity when before the trials of this world and the pending death charges that loomed over their heads. As we meditate on Jesus being Crowned with Thorns, we are to meditate on His moral courage so that we can grow in moral courage, especially in the midst of suffering, great or small.

The Scriptural Rosary is:

1. The Third Sorrowful Mystery is: Crowning with Thorns
1. Pater Noster …
2. And they stripped him and put a scarlet robe on him, and plaiting a crown of thorns, they put it on his head, and put a reed in his right hand. (Matthew 27:28-29a)
1. Ave Maria …
3. And kneeling before him they mocked him, saying, “Hail, King of the Jews!” (Matthew 27:29b)
1. Ave Maria …
4. And they spat upon him and took the reed and struck him on the head. (Matthew 27:30)
1. Ave Maria …
5. Pilate again went outside and said, “I bring Him out to you, that you may know that I find no guilt in Him." (John 19:4)
1. Ave Maria …
6. Jesus therefore came forth, wearing the crown of thorns and the purple cloak. (John 19:5)
1. Ave Maria …
7. Many were astonished at him, his appearance was so marred beyond human semblance, and his form beyond that of the sons of men. (Isaiah 52:14)
1. Ave Maria …
8. He had no form or comeliness that we should look at him, and no beauty that we should desire him. (Isaiah 53:2)
1. Ave Maria …
9. He was despised and rejected by men, a man of sorrows and acquainted with grief. And, as one from whom men hide their faces, he was despised, and we esteemed him not. (Isaiah 53:3)
1. Ave Maria …
10. And Pilate said to them, "Behold the man!" But they cried out, "Away with Him! Crucify Him!" (John 19:5, 15)
1. Ave Maria …
11. "Shall I crucify your king?" And the chief priests answered, "We have no king but Caesar." Then he handed Him over to them to be crucified. And so, they took Jesus and led Him away. (John 19:15-16)
1. Ave Maria …
12. O My Jesus …
13. Gloria Patri …

*Li, C.-Y.; Devappa, R. K.; Liu, J.-X.; Lv, J.-M.; Makkar, H. P. S.; Becker, K. Toxicity of Jatropha Curcas Phorbol Esters in Mice. Food Chem. Toxicol. 2010, 48 (2), 620–625.