613 Mitzvot
Negative Mitzvah 13
Not to plant Asherah

Devarim (Deuteronomy) 16:21

The Asherah was a wooden image, or a pillar representing Ashtoret, a sensual Canaanite goddess, probably usually set up in a grove. The Assyrian version of this name is Ishtar. She was known as the queen of heaven.

Yirmeyahu (Jeremiah) 7:18  The children gather wood, and the fathers kindle the fire, and the women knead their dough, to make cakes to the queen of heaven, and to pour out drink offerings unto other elohim, that they may provoke me to anger.

The King James Version translates this groves. Often pagan worship is done in forests.

1 Melakhim (Kings) 14:23  For they also built them high places, and pillars, and Asherim, on every high hill, and under every green tree;

The children of Yisra'el were commanded to destroy these asherah when they entered the Promised Land. They were to cut down the Asherim and burn them.

Devarim (Deuteronomy) 12:2,3) You shall surely destroy all the places in which the nations that you shall dispossess served their gods, on the high mountains, and on the hills, and under every green tree: and you shall break down their altars, and dash in pieces their pillars, and burn their Asherim with fire; and you shall cut down the engraved images of their gods; and you shall destroy their name out of that place.

Devarim (Deuteronomy) 7:5  But thus shall you deal with them: you shall break down their altars, and dash in pieces their pillars, and hew down their Asherim, and burn their engraved images with fire.

In addition, these Asherah trees were decorated. The Asherah was a tree that decorated with woven (perhaps from boughs of the tree), silver and gold hangings on it.

2 Melakhim (Kings) 23:7  He broke down the houses of the sodomites, that were in the house of YHVH, where the women wove hangings for the Asherah.

Perhaps these women were priestesses for Ashterot.

Yirmeyahu (Jeremiah) 10:3,4 For the customs of the peoples are vanity; for one cuts a tree out of the forest, the work of the hands of the workman with the axe. They deck it with silver and with gold; they fasten it with nails and with hammers, that it not move.

The "Asherah" is was planted near the house of idol- worship in order to make the area more beautiful. We are forbidden to plant trees near the altar of the Temple - the Beit HaMikdash. The Torah wants our service of YHVH to be holy and special. It should, in no way, resemble any form of idol-worship. Because of this, there were no trees planted on the Temple site. As with the "Matzevah" (Negative Mitzvah 11) and the "kneeling stone" (Negative Mitzvah 12), so, too, the "Asherah" is not to be used, even if our intention is for the service of YHVH. These are not allowed because they are connected with idol worship.

The Even HaAzel points the context of this mitzvah among the customs of appointing judges: 'This also explains the Talmud's statement (Sanhedrin 7a), the the reason that the Torah places this law immediately following the law regarding the appointment of judges, is to teach us that 'Whoever appoints an unqualified judge it is as if he planted an asheira near the altar.' Often, we see people appointed to positions of authority because of their external appearance, charm and oratorical prowess, instead of their knowledge, integrity and fear of Heaven...' (Even HaAzel)

The Even HaAzel also says, 'To seek to beautify the Holy Temple by planting trees around it is an insult to the holiness of the place, whose beauty derives from itself and not from external 'landscaping.'

This applies to our own lives as well, since we are a temple for YHVH (1 Corinthians 3:16, 6:19) In the same way, Our focus should not be on the external appearances. Our true value doesn't come from 'landscaping', i.e. charm, speaking skills, position or appearance, but rather from the holiness that is given to us by YHVH.

Let your beauty be not just the outward adorning of braiding the hair, and of wearing jewels of gold, or of putting on fine clothing; but in the hidden person of the heart, in the incorruptible adornment of a gentle and quiet spirit, which is in the sight of Elohim very precious. For this is how the holy women before, who hoped in YHVH also adorned themselves, being in subjection to their own husbands:' (1Kefa/Peter 3:3-5)

This verse shouldn't only apply to women' Men can kept caught up in the outward things as well.  They can get wrapped up in getting high paying positions, or fancy cars. They may want to work out to get that muscle-bound appearance, and neglect developing their spiritual strength.

1 Timothy 4:8 
For bodily exercise has some value, but godliness has value in all things, having the promise of the life which is now, and of that which is to come.

1 Shemu'el (Samuel) 16:7  But YHVH said to Shemu'el, "Don't look on his face, or on the height of his stature; because I have rejected him: for YHVH sees not as man sees; for man looks at the outward appearance, but YHVH looks at the heart."

Shalom v'brakhot
Moreh Chizkiyah Shlomo
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Be libi tzavanti imratecha le ma'an lo echta lach.
(Tehillim 119:11)