Bignonia, commonly called Crossvine or Cross Vine, are easy-to-grow North American native flowering vines that cover fences, arbors and other structures quickly. They produces LOADS of fragrant, brightly colored, trumpet-shape flowers in spring, and repeat again in mid to late summer in our north-central Georgia gardens. The attractive foliage remains evergreen in the South turning to reddish-purple in fall, with subsequent leaf drop in the northern regions where it will grow, USDA Zones 6a-9b. Find Your Zone >
Crossvines are ideal for use to climb up and on fences, trellises, posts and mailboxes, or over an arch, arbor or any other structure that might benefit from or support this magnificent fragrant vine. They are also useful to climb trees, where early flowering is especially noticeable.
Another great thing about Crossvine is that, unlike some other vines which only grow along the top of a fence, Crossvine will grow to the top and then cascade down to the ground to totally cover the fence, providing a solid barrier. if you have an old and ugly chain link fence you want to turn into a beautiful "live wall" it doesn't get much better than Crossvine.
Here's a breakdown of what you need to know for how to plant and grow Crossvines...
Cultural Preferences
Soil Preferences
Crossvines adapt well to a wide range of soils. They grow best in a moist but well-drained, organically rich soil, however will tolerate constantly soggy soils.
Testing Soil Drainage
If you are uncertain about soil drainage in the area you intend to plant, it's well worth taking the time to test the drainage before planting. To test soil drainage, dig a hole 12" wide by 12" deep in the planting area. Fill the hole with water and let it drain. Then, after it drains, fill it with water again, but this time clock how long it takes to drain. In well-drained soil the water level will go down at a rate of about 1 inch an hour. A faster rate, such as in loose, sandy soil, may signal potentially dry site conditions. A slower rate indicates poor draining soil and could be a caution you might need to improve drainage, plant in a raised mound or bed, or look for plants that are more tolerant of wet or boggy conditions.
Soil Ph
Crossvines grow best in a slightly acid to slightly alkaline soil ranging from 6.5 to 8.0 on the pH scale. Most average garden soils fall between a pH range of 6.0 to 7.0.
Testing Soil pH
Soil pH is a measurement of the alkalinity or acidity of soil and is measured on a scale of 1-14, with 7 as the neutral mark. Any measurement below 7 indicates acid soil conditions, and anything above 7 indicates alkaline. If you're unsure about the pH of your soil, and whether or not it is suitable for growing Crossvine, it's a good idea to test the pH in the planting area. You can quickly test soil pH with an inexpensive soil pH tester probe. To raise the pH (make more alkaline) you can add pelletized limestone to the soil. To lower the pH (make more acid) you can apply Soil Sulfur, Aluminum Sulfate, or Chelated Iron. Adding organic compost to the soil or using compost as mulch can also help to increase acidity and maintain acid soil conditions.
Learn More: What is Soil pH and How To Adjust It?
Light Preferences
Crossvines grow and flower best in full to mostly sun, however will tolerate some shade. We have one planted in almost full shade and it still produces flowers, but only about a third as many as the ones growing in full sun. With at least 6 hours of direct sunlight per day you can expect full flowering and repeat bloom.
Planting Crossvines In The Ground
(Scroll down to see planting instructions for containers and pots)
Step 1
Start by digging your planting hole at least two to three times as wide and as deep as the height of the rootball of your plant. The wider the hole the better. Place native soil removed from planting hole around the perimeter of the hole, in a wheel barrow, or on a tarp.
Step 2
Depending on the type, fertility and porosity of the soil in the planting area you might need to add a soil amendment to the native soil removed from the planting hole. When planting Crossvines in dense clay or poor quality soils it is beneficial to thoroughly mix in some good organic matter such as bagged top soil, aged compost, and/or a good planting mix at a 25-50% ratio with the soil removed from the planting hole. When planting in very sandy or quick-draining soil mixing in some top soil, peat moss and/or compost will help to retain moisture in the soil. When planting in average, well-drained moist soil there is no need for adding a soil amendment.
Step 3
To remove your vine from the container it was growing in, it's best to cut the container away. After having removed the plant from the container, gently loosen some feeder roots around the surface of the rootball.
Step 4
Set your vine in the planting hole so that the top edge of the rootball is at or slightly above ground level to allow for settling. It may be necessary to place some of your backfill soil mixture in the bottom of the hole to achieve proper planting height.
Step 5
After setting your vine in the planting hole, use one hand to hold the plant straight while using your other hand to begin backfilling the soil mixture around the root ball, tamping as you go to remove air pockets. When you have filled the hole to the halfway point you can soak the soil. Then continue backfilling to the top edge of the root ball. To avoid suffocating your plant, do not put any soil on top of the root ball.
Step 6 (Optional)
When planting your Crossvine in a site far away from a water source, you can use remaining soil mixture to build a water retaining berm (catch basin / doughnut) that is 2 to 3 inches high around the outside perimeter of the planting hole, as shown in the illustration above. This basin will help to collect water from rainfall and irrigation which can help reduce the need for hand-watering. The berm can be removed after a growing season or two.
Step 7
After planting, deeply water the planting area and the rootball. For an extra boost, you can also water your newly planted vine with a solution of Root Stimulator, which stimulates early root formation and stronger root development, promoting greener, more vigorous plants.
Step 8
Apply a 1 to 2 inch layer of cured shredded wood mulch or bark or a 1 to 2 inch layer of pine straw around your newly planted vines. Avoid using freshly chipped or shredded wood for mulch until it has cured in a pile for at least 6 months, a year is better.
Planting Bignonia Crossvines In Containers
Though not quite as cold hardy in containers, Crossvines are ideal for use in pots and other containers.
When growing in pots Crossvines appreciate a moist but well-drained soil. Therefore, plant in a container or pot that has a drainage hole(s) and use a quality potting soil or potting mix, or a 50/50 combination thereof for planting.
Make sure to choose a container with drainage holes at the bottom and one that is large enough to allow for many years of growth before shifting up to a larger size container. This might mean your planting pot would be 10 inches or more in width than the root ball of your plant.
Container color will matter as well. Not only will you want to pick a color of container that goes well with the foliage and flower color of your Crossvine, you'll also want to pick a container that matches the style of your home or other structures and other plants in the surrounding environment.
Many nursery & garden centers offer a wide variety of containers to choose from. Before heading out to buy a container take pictures of your home and the surrounding environment. Doing so will help you to choose just the right color and style.
Container Planting Instructions
Step 1
Before filling your container with the soil mix, we recommend lining the bottom with shade cloth or a porous landscape fabric. This will keep the drain holes from becoming stopped up with soil.
Step 2
To remove your vine from the container it was growing in, it's best to cut the container away. After having removed the plant from the container, gently loosen some feeder roots around the surface of the rootball.
Step 3
Pour a small amount of your soil mixture in the bottom of the container. Set your plant in the container and make necessary adjustments by adding or removing some soil so that the top edge of the root ball will sit 1" below the rim of the container.
Step 4
Backfill with your potting soil around root ball, tamping as you go, until the level of potting soil is even with the top edge of root ball, as shown in the illustration above.
Step 5
Water thoroughly until water starts to drain from the holes in the bottom of the container. Add more potting mix if settling occurs during watering.
Step 6 (Optional)
Apply a 1/2" layer of wood chips or sphagnum moss to soil surface to help conserve moisture.
How To Care For Bignonia Crossvine
Feeding - Watering - Pruning
Crossvines aren't heavy feeders however will benefit from a feeding after flowering in spring with a slow-release shrub & tree fertilizer or an organic plant food. Cease fertilization two months prior to the typical first-frost date in your area. Iron and/or soil sulfur can be applied for deep greening of foliage.
How To Water Bignonia Crossvines
Crossvines grow best in a consistently moist but well-drained, organically rich soil, however will tolerate constantly soggy soils or brief dry periods.
After Planting
Immediately after planting deep soak the soil in the planting area to a depth of at least 6 inches. For an extra boost, you can also water your newly planted Crossvine with a solution of Root Stimulator, which stimulates early root formation and stronger root development, promoting greener, more vigorous plants.
During First Growing Season
In average garden soil you should not have to water your newly planted Crossvine every day. In the absence of sufficient rainfall, water only as needed to keep the rootball and surrounding soil damp to moist. Keep in mind that deep soaking less frequently is much better than splashing just a little water on the plants every day. Plants planted during the winter dormant season, when not actively growing and evaporation is much slower, will require much less water.
Thereafter
When established, Crossvines are quite drought tolerant. That said, if during a drought you see new leaves wilting this could be an indicator your plants could use a good, deep soaking.
Note: When watering with an automated irrigation system it's best to set your timer to water during the early morning hours and not in the late evening or at night, which can lead to the onset of fungus and other foliar diseases. Check soil moisture within a few days after planting and adjust your irrigation system accordingly to provide only enough water to keep soil moist, but not soggy.
How To Prune Bignonia Crossvine Plants
Crossvine does not require pruning, however can be pruned as needed to keep the vine tidy and/or in bounds. If desired, use bypass hand pruners immediately after spring flowering to remove stray shoots or to shape or reduce the size of the vine.
Note: Cease pruning about two months prior to the average first-frost date in your area.