Illustrating the great harmony in Catholic life between seasonal customs and the liturgical year, the Church instituted at this time of year the blessing of Herbs in connection with Our Lady’s glorious Assumption into Heaven. This blessing found in the Rituale Romanum was only to be offered on this particular day and was observed for centuries before the dogma of the Assumption was infallibly defined by Pope Pius XII in 1950. Gregory DiPippo in a 2015 article at New Liturgical Movement wrote:
The blessing originated in Germany and is first attested in the 10th century; one version of it or another is found in a great many of the liturgical books which contain blessings of this sort. In the 1614 Roman Ritual of Pope Paul V, it consists of a psalm, a series of versicles and responses, three prayers, and the blessing, after which the flowers are sprinkled with holy water; the blessing is supposed to be done before the principal Mass of the day.
Why the blessing of Herbs? It is connected with an ancient tradition that states that after Our Lady’s Assumption into Heaven, beautiful and sweet-smelling flowers began to grow out of the stone sarcophagus, confirming to the Apostles that she had truly been assumed by her divine son. Regardless of whether this manifestation of flowers actually occurred, our custom for keeping Assumption Day as a day for blessing herbs helps unite us to the Apostles and centuries of Catholics who knew of and believed in her triumph over death. Like Our Lady, we too look forward to our eventual Resurrection, confident in the mercy of God if we preserve in the state of sanctifying grace until death.
Herbs also show a connection with the life of the average agrarian Catholic who would at this time be observing the fall harvest. Father Weiser in his opus magnum Handbook of Christian Feasts and Customs—which all Catholics should read—notes this connection especially led Hungary and Poland to observe Assumption Day as a celebration of God’s blessings upon the harvest:
In the Christian era the custom of celebrating a thanksgiving harvest festival began in the High Middle Ages. For lack of any definite liturgical day or ceremony prescribed by the Church, various practices came to be observed locally. In many places, as in Hungary, the Feast of the Assumption included great thanksgiving solemnities for the grain harvest. Delegates from all parts of the country came for the solemn procession to Budapest, carrying the best samples of their produce. A similar ceremony was observed in Poland, where harvest wreaths brought to Warsaw from all sections were bestowed on the president in a colorful pageant. These wreaths (wieniec), made up of the straw of the last sheaf (broda), were beautifully decorated with flowers, apples, nuts, and ribbons, and blessed in churches by the priests.
The blessing of herbs is preserved in the 1962 and 1964 Rituale Romanum (which are nearly identical aside from some alterations to the Rite of Marriage). A PDF of the 1962 Rituale may be found online and the blessing of herbs may be said by any priest. Ask your priest in advance to publicly bless herbs on Assumption Day and invite the faithful to bring their own herbs from home for this unique tradition.
Taken from the Rituale Romanum:
17. BLESSING OF HERBS on the Assumption of the Blessed Virgin Mary
{This blessing comes from Germany, and formulas for it are found
as early as the tenth century. The blessing of herbs was reserved only
to the feast of the Assumption. Herbs had not our restricted English
meaning but included all kinds of cultivated and wild flowers,
especially those which in some way had a symbolic relation to our Lady.
The people brought herbs to church on her feast not only to secure for
themselves another blessed object, but also to make of the occasion a
harvest festival of thanksgiving to God for His great bounty manifested
in the abundant fruits of the earth. The herbs were placed on the altar,
and even beneath the altar-cloths, so that from this close contact with
the Eucharist they might receive a special consecration, over and above
the ordinary sacramental blessing of the Church.}
After the Asperges if it is a Sunday, otherwise immediately
before Mass, the priest, standing before the altar and facing the people
who hold the herbs and fruits in their hands, says in a clear voice:
P: Our help is in the name of the Lord.
All: Who made heaven and earth.
Psalm 64
P: To you we owe our hymn of praise, O God, in Sion; to you must vows be fulfilled, you who hear prayers.
All: To you all flesh must come* because of wicked deeds.
P: We are overcome by our sins; * it is you who pardon them.
All: Happy the man you choose, * and bring to dwell in your courts.
P: May we be filled with the good things of your house, * the holy things of your temple.
All: With awe-inspiring deeds of justice you answer us, * O God our Savior,
P: The hope of all the ends of the earth * and of the distant seas.
All: You set the mountains in place by your power, * you who are girt with might;
P: You still the roaring of the seas, * the roaring of their waves and the tumult of the peoples.
All: And the dwellers at the earth's ends are in fear at your marvels; * the farthest east and west you make resound with joy.
P: You have visited the land and watered it; * greatly have you enriched it.
All: God's watercourses are filled; you have prepared the grain. * Thus have you prepared the land:
P: Drenching its furrows, * breaking up its clods,
All: Softening it with showers, * blessing its yield.
P: You have crowned the year with your bounty, * and your paths overflow with a rich harvest;
All: The untilled meadows overflow with it, * and rejoicing clothes the hills.
P: The fields are garmented with flocks and the valleys blanketed with grain. * They shout and sing for joy.
All: Glory be to the Father.
P: As it was in the beginning.
P: The Lord will be gracious.
All: And our land will bring forth its fruit.
P: You water the mountains from the clouds.
All: The earth is replenished from your rains.
P: Giving grass for cattle.
All: And plants for the benefit of man.
P: You bring wheat from the earth.
All: And wine to cheer man's heart.
P: Oil to make his face lustrous.
All: And bread to strengthen his heart.
P: He utters a command and heals their suffering.
All: And snatches them from distressing want.
P: Lord, heed my prayer.
All: And let my cry be heard by you.
P: The Lord be with you.
All: May He also be with you.
Let us pray.
Almighty everlasting God, who by your word alone brought into
being the heavens, earth, sea, things seen and things unseen, and
garnished the earth with plants and trees for the use of man and beast;
who appointed each species to bring forth fruit in its kind, not only
for the food of living creatures, but for the healing of sick bodies as
well; with mind and word we urgently call on you in your great kindness
to bless
these various herbs and fruits, thus increasing their natural powers
with the newly given grace of your blessing. May they keep away disease
and adversity from men and beasts who use them in your name; through
Christ our Lord.
All: Amen.
Let us pray.
God, who through Moses, your servant, directed the children of
Israel to carry their sheaves of new grain to the priests for a
blessing, to pluck the finest fruits of the orchard, and to make merry
before you, the Lord their God; hear our supplications, and shower
blessings
in abundance upon us and upon these bundles of new grain, new herbs,
and this assortment of produce which we gratefully present to you on
this festival, blessing
them in your name. Grant that men, cattle, flocks, and beasts of burden
find in them a remedy against sickness, pestilence, sores, injuries,
spells, against the fangs of serpents or poisonous creatures. May these
blessed objects be a protection against diabolical mockery, cunning, and
deception wherever they are kept, carried, or otherwise used. Lastly,
through the merits of the blessed Virgin Mary, whose Assumption we are
celebrating, may we all, laden with the sheaves of good works, deserve
to be taken up to heaven; through Christ our Lord.
All: Amen.
Let us pray.
God, who on this day raised up to highest heaven the rod of
Jesse, the Mother of your Son, our Lord Jesus Christ, that by her
prayers and patronage you might communicate to our mortal nature the
fruit of her womb, your very Son; we humbly implore you to help us use
these fruits of the soil for our temporal and everlasting welfare, aided
by the power of your Son and the prayers of His glorious Mother;
through Christ our Lord.
All: Amen.
And may the blessing of almighty God, Father, Son,
and Holy Spirit, come upon these creatures and remain always.
All: Amen.
They are sprinkled with holy water and incensed.