(ז) כִּ֚י יְהֹוָ֣ה אֱלֹהֶ֔יךָ מְבִֽיאֲךָ֖ אֶל־אֶ֣רֶץ טוֹבָ֑ה אֶ֚רֶץ נַ֣חֲלֵי מָ֔יִם עֲיָנֹת֙ וּתְהֹמֹ֔ת יֹצְאִ֥ים בַּבִּקְעָ֖ה וּבָהָֽר׃ (ח) אֶ֤רֶץ חִטָּה֙ וּשְׂעֹרָ֔ה וְגֶ֥פֶן וּתְאֵנָ֖ה וְרִמּ֑וֹן אֶֽרֶץ־זֵ֥ית שֶׁ֖מֶן וּדְבָֽשׁ׃ (ט) אֶ֗רֶץ אֲשֶׁ֨ר לֹ֤א בְמִסְכֵּנֻת֙ תֹּֽאכַל־בָּ֣הּ לֶ֔חֶם לֹֽא־תֶחְסַ֥ר כֹּ֖ל בָּ֑הּ אֶ֚רֶץ אֲשֶׁ֣ר אֲבָנֶ֣יהָ בַרְזֶ֔ל וּמֵהֲרָרֶ֖יהָ תַּחְצֹ֥ב נְחֹֽשֶׁת׃ (י) וְאָכַלְתָּ֖ וְשָׂבָ֑עְתָּ וּבֵֽרַכְתָּ֙ אֶת־יְהֹוָ֣ה אֱלֹהֶ֔יךָ עַל־הָאָ֥רֶץ הַטֹּבָ֖ה אֲשֶׁ֥ר נָֽתַן־לָֽךְ׃
(7) For your God יהוה is bringing you into a good land, a land with streams and springs and fountains issuing from plain and hill; (8) a land of wheat and barley, of vines, figs, and pomegranates, a land of olive trees and honey; (9) a land where you may eat food without stint, where you will lack nothing; a land whose rocks are iron and from whose hills you can mine copper. (10) When you have eaten your fill, give thanks to your God יהוה for the good land given to you.
Deuteronomy 8:8 introduces the Israelites to seven species of produce they'll encounter in the land: wheat and barley, (grape)vines, figs, and pomegranates, olive trees and (date)honey. These seven species become essential to the Temple Sacrifice, as attested in the Mishnah:
(ג) אֵין מְבִיאִין בִּכּוּרִים חוּץ מִשִּׁבְעַת הַמִּינִים. לֹא מִתְּמָרִים שֶׁבֶּהָרִים, וְלֹא מִפֵּרוֹת שֶׁבָּעֲמָקִים, וְלֹא מִזֵּיתֵי שֶׁמֶן שֶׁאֵינָם מִן הַמֻּבְחָר. אֵין מְבִיאִין בִּכּוּרִים קֹדֶם לָעֲצֶרֶת. אַנְשֵׁי הַר צְבוֹעִים הֵבִיאוּ בִכּוּרֵיהֶם קֹדֶם לָעֲצֶרֶת, וְלֹא קִבְּלוּ מֵהֶם, מִפְּנֵי הַכָּתוּב שֶׁבַּתּוֹרָה (שמות כג) וְחַג הַקָּצִיר בִּכּוּרֵי מַעֲשֶׂיךָ אֲשֶׁר תִּזְרַע בַּשָּׂדֶה:
(3) Bikkurim are brought only from the seven species. Not from dates grown on hills, nor from [the other species] grown in the valley, nor from olives that are not choice. Bikkurim are not to be brought before Shavuot. The people from Mt. Zevoim brought bikkurim prior to Atzeret (Shavuot), but they did not accept from them, on for it is written in the Torah: “And the festival of the harvest, the first-fruits of your labors, which you have sown in the field” (Exodus 23:16).
Wheat: the first of the seven species is associated with Shavu'ot as far back as Exodus:
We know that wheat is harvested later than barley from the plague of hail in Mitsrayim:
(יח) הִנְנִ֤י מַמְטִיר֙ כָּעֵ֣ת מָחָ֔ר בָּרָ֖ד כָּבֵ֣ד מְאֹ֑ד אֲשֶׁ֨ר לֹא־הָיָ֤ה כָמֹ֙הוּ֙ בְּמִצְרַ֔יִם לְמִן־הַיּ֥וֹם הִוָּסְדָ֖הֿ וְעַד־עָֽתָּה׃ (כה) וַיַּ֨ךְ הַבָּרָ֜ד בְּכׇל־אֶ֣רֶץ מִצְרַ֗יִם אֵ֚ת כׇּל־אֲשֶׁ֣ר בַּשָּׂדֶ֔ה מֵאָדָ֖ם וְעַד־בְּהֵמָ֑ה וְאֵ֨ת כׇּל־עֵ֤שֶׂב הַשָּׂדֶה֙ הִכָּ֣ה הַבָּרָ֔ד וְאֶת־כׇּל־עֵ֥ץ הַשָּׂדֶ֖ה שִׁבֵּֽר׃ (לא) וְהַפִּשְׁתָּ֥ה וְהַשְּׂעֹרָ֖ה נֻכָּ֑תָה כִּ֤י הַשְּׂעֹרָה֙ אָבִ֔יב וְהַפִּשְׁתָּ֖ה גִּבְעֹֽל׃ (לב) וְהַחִטָּ֥ה וְהַכֻּסֶּ֖מֶת לֹ֣א נֻכּ֑וּ כִּ֥י אֲפִילֹ֖ת הֵֽנָּה׃
(18) This time tomorrow I will rain down a very heavy hail, such as has not been in Egypt from the day it was founded until now. (25) Throughout the land of Egypt the hail struck down all that were in the open, both human and beast; the hail also struck down all the grasses of the field and shattered all the trees of the field. יהוה.”— (31) Now the flax and barley were ruined, for the barley was in the ear and the flax was in bud; (32) but the wheat and the emmer*emmer A kind of wheat. were not hurt, for they ripen late.—
Barley is mentioned five times in the Book of Ruth, much of which takes place during the barley harvest:
When shedSo in many Heb. mss; most mss. read “he.” got back to the town, (16) she came to her mother-in-law, who asked, “How is it with you, daughter?” She told her all that the man had done for her; (17) and she added, “He gave me these six measures of barley, saying to me, ‘Do not go back to your mother-in-law empty-handed.’” (18) And Naomi said, “Stay here, daughter, till you learn how the matter turns out. For the man will not rest, but will settle the matter today.”
Grapes: the first "vine" in Torah is a grape vine, though in Mitsrayim rather than the land of Israel:
Figs first appear in the Garden of Eden; their leaves as the first clothes. Is it possible that the fruit of the tree of knowledge was a fig?
Pomegranates are first referenced as embroidered decorations for Aharon's robe:
The scouts bring pomegranates, grapes and figs, to prove to the Israelites that the land is fertile and full of the fruits that the Sinai wilderness lacks (about which they complain in Numbers 20:5!):
Olive oil is first cited as fuel for the Ner Tamid:
Dates: One might ask, how do we get from the vague "devash" i.e. honey in Deuteronomy, to the specific "temarim" i.e. dates that are not grown on hills in the Mishnah?
Because of tithing:
Bee honey cannot possibly be subject to tithing, because it is not produced by a plant. If gifts are restricted to produce subject to tithing, therefore devash-honey must refer to dates.
Why not dates from the hills? See Menachot 84b:
מתמרים שבהרים ולא מפירות שבעמקים אמר עולא אם הביא לא קידש
bring them from dates that grow in the mountains, and one may not bring them from produce that grows in the valleys. Such produce is of inferior quality and may not be used. Ulla says: Even if one did bring such produce, he does not thereby consecrate it, i.e., it does not attain the consecrated status of first fruits.
The text not in bold,i.e. that dates growing in the mountains are of inferior quality, is Steinsaltz's commentary:
Rebbetzin Chana Bracha Siegelbaum teaches that the Kabbalist Arizal connected each of the seven species to each of the lower spheres.
Read more of her post at Canfei Nesharim:
https://canfeinesharim.org/eikev-shivat-haminim-the-seven-fruits-of-israel/
If that site doesn't work, try B'erot Bat Ayin:
https://www.berotbatayin.org/wp-content/uploads/2018/01/Herb7Fruits.pdf