Ask Mr. Smarty Plants

Acer palmatum, Japanese maple is non-native to North America, which puts it out of our area of expertise as well as our Native Plant Database, so we can't comment on that. Both it and the holly are tolerant of shade so that is probably why they are doing okay under the pine trees. We were curious about what pines you had, and checked on the 10 members of the Pinus genus native to Texas. Of these, 8 were native to very far West Texas or very far East Texas. Pinus echinata (shortleaf pine) and Pinus taeda (loblolly pine) both grow in Northeast Texas, not too far from Tarrant County. Of course, you can buy any plant and plant it wherever you wish, but the plant won't necessarily prosper where the soil, climate or rainfall are not what that plant is accustomed to. 

When considering plants to go under pine trees, you not only have to look at the shade, but also the litter factor; that is, pine needles falling virtually year-round, even though the tree is evergreen. Those  needles will contribute to the acidity of the soil, whereas many of the areas in Texas, including Tarrant County, have mostly alkaline, clay soils. Because of this acidity, pine trees can sometimes exhibit allelopathy, which is the emission of substances intended to inhibit competing plants. Another consideration is water: the pines have shallow roots and will soak up all the water they can get. So, before we recommend any plants native to your area to go under those trees, let us make some recommendations of action to take first: (1) Limb up the pines, trimming back lower branches both to cut down on the number of needles and also to let more light and rainwater in under those branches. (2) Spread an organic topsoil, or, better, a good quality compost about 3 or 4 inches deep over the area. This protects the shallow tree roots, adds nutrients to the soil, and gives your new plants a slightly less acidic environment. (3) Rake up pine needles about once a week with a small rake that can be maneuvered between your in-ground plants. If you have a compost pile, they could go in that. If you want to make a path, they are excellent for lining paths. (4) For at least the first year or so your new plants are in the ground, keep them watered beneath the pines, remembering that the pines are moisture-grabbers.

Now, for plants to go beneath those pines, we will go to our Recommended Species for North Central Texas, and choose some native shrubs, ferns, and perennial herbaceous blooming plants for part shade (2 to 6 hours of sun daily) or shade (less than 2 hours of sun). Follow the links to our page on individual plants to learn how big they get, how and when to propagate, when and what color they bloom, etc. 

Shrubs for Under Pine Trees in Grapevine TX:

Callicarpa americana (American beautyberry)

Ilex vomitoria (yaupon)

Perennial Flowering Plants for Under Pine Trees in Grapevine TX:

Aquilegia canadensis (red columbine)

Asclepias tuberosa (butterfly milkweed)

Echinacea purpurea (eastern purple coneflower)

Melampodium leucanthum (plains blackfoot)

Salvia roemeriana (cedar sage)

Ferns for Under Pine Trees in Grapevine TX:

Adiantum capillus-veneris (common maidenhair)

Athyrium filix-femina ssp. asplenioides (asplenium ladyfern)

Polystichum acrostichoides (Christmas fern)

From our Native Plant Image Gallery:

Pinus echinata

Pinus taeda

Callicarpa americana

Ilex vomitoria

Aquilegia canadensis

Asclepias tuberosa

Echinacea purpurea

Melampodium leucanthum

Salvia roemeriana

Adiantum capillus-veneris

Athyrium filix-femina ssp. asplenioides

Polystichum acrostichoides