The Christmas carol “Deck the Halls: has the lyric, “‘Tis the season to be jolly.” A riddle was cited in print in 1978:
 
Q: What did one grape say to the other grape?
A: ‘Tis the season to be jelly, fa-la-la-la-la-la-la-la-la.
 
A different question was posted on Twitter on December 25, 2009:
 
Q: What did the grape say to the peanut butter?
A: “‘Tis the season to be jelly!”
 
     
Wikipedia: Deck the Halls
“Deck the Halls” or “Deck the Hall” (which is the original version of the lyrics) is a traditional Christmas, yuletide, and New Years’ carol. The melody is Welsh dating back to the sixteenth century, and belongs to a winter carol, “Nos Galan”, while the English lyrics, written by Thomas Oliphant, date to 1862.
(...)
Deck the hall with boughs of holly,
Fa, la, la, la, la, la, la, la, la!
‘Tis the season to be jolly,
Fa, la, la, la, la, la, la, la, la!
         
3 January 1978, St. Louis (MO) Post-Dispatch, “Jokes by You,” pg. 5G, col. 1:
Q: What did one grape say to the other grape?
A: ‘Tis the season to be jelly, fa-la-la-la-la-la-la-la-la.
Allan Taylor
 
1 May 1984, St. Louis (MO) Post-Dispatch, “Jokes by You,” pg. 4C, col. 5:
Q: What did one grape say to another?
A: “‘Tis the season to be jelly, Fa-la-la-la-la-la-la-la-la.”
Ann Coe
 
5 November 1990, Indiana (PA) Gazette, “Mighty Funny’s Mini Jokes,” The Mini Page, pg. 3, col. 2:
Q: What did one grape say to the other?
A: ‘Tis the season to be jelly!
 
Google Books
Totally Cool Clean Jokes for Kids
By Bob Phillips
Eugene, OR: Harvest House Publishers
1997
Pg. 39:
Eugenia: Why does Santa’s belly jiggle when he laughs?
Tammy: I pass.
Eugenia: ‘Tis the season to be jelly
 
Google Groups: alt.humor.puns
“Puns of the Weak” 12/22/00
Stan Kegel
12/23/00
(...)
What did the grape say to the raisin? ‘Tis the season to be jelly.(ArcaMax)
 
Google Books
Giggles
By Charles Keller
New York, NY: Sterling Publishing Company, Inc.
2007
Pg. 325:
What did the big grape say to the little grape on Christmas?
“‘Tis the season to be jelly. “
 
Twitter
PolarCoug‏
@PolarCoug
What did the grape say to the raisin?
‘Tis the season to be jelly.
10:37 PM - 21 Dec 2009
 
Twitter
goode enuff‏
@goodeenuff
What did the grape say to the peanut butter?
“‘Tis the season to be jelly!”
10:39 PM - 25 Dec 2009
     
Google Books
Christmas Crackers
By Matt Wilce
Lulu Press (Lulu.com)
2012
Pg. ?:
What did the strawberry say to the lemon?
“‘Tis the season to be jelly!”
 
Google Books
Gigglers: Christmas Jokes
By Toby Reynolds
London, UK: Scholastic Fiction
2015
Pg. 57:
Q. What did the grape say to the raisin?
A. ‘Tis the season to be jelly!
 
Twitter
Scotty Servis‏
@scotty_servis
#tistheseason Q:What did the peanut butter say to the grape? A: Tis the season to be jelly… 😃
12:37 AM - 8 Dec 2017 from Anaheim, CA