If you are a gardener, you probably have shaded areas that can be difficult to fill, particularly with food plants. Most vegetables require sunlight, and while we can place most plants in the preferred locations, sometimes we just run out of space.
Sweet potato is an interesting vegetable because while it grows best in full sun, it will also grow in shade. A few short hours of soft early light can have the plant looking fantastic, but will it grow sweet potatoes.
Sweet potato vine will produce tubers when grown in shade, but they will be fewer and spread further apart than plants in full sun. The plant is still worth growing as you will find below.
Will shade limit a sweet potato harvest?
Shade will play a large part in the harvest size of sweet potatoes. Our experience tells us that while the vines look really vibrant and healthy, they chase the sunlight, and this takes energy away from tuber production.
We do find sweet potato tubers, but as mentioned earlier, they are spread well apart and make the harvest process more challenging. We don’t look for the tubers in this area, and any that do grow are left to re-grow the following year.
This gives us a wild crop each year of fresh green leaves for the kitchen and for occasional fodder for the chickens.
Will sweet potato vine take longer to grow in the shade?
The seasonal time for sweet potato vine growth in shade is similar to a sun-grown plant however, it can be difficult to tell when the tubers are ready to be picked.
We have found the sweet potato flowers are less prevalent in shady zones, and we cannot find any reputable information whether this indicative of tuber growth or not. The sweet potato vines we have in full sun flower regularly.
Will sweet potato vine be healthy in shady spots?
The sweet potato plant grown in shade can be spectacularly healthy if the soil conditions are suitable and reasonable amounts of moisture are available.
We have some sweet potato plants growing under a medium size mango tree. The area beneath the canopy is covered with leaf litter, and below that is a blanket of timber offcuts and small branches used as mulch.
We live in the wet tropics of northeast Australia where this kind of mulch breaks down rapidly through microscopic bacterial and fungal activity. This feeds the tree, the ginger, turmeric, sweet potato, galangal, and katuk all at the same time.
This growing method delivers very healthy plants, including sweet potato; but as noted above, the vine tends to chase sunlight, so we get small harvests from the shaded zones.
Why grow sweet potato in shaded areas?
As the image shows, the sweet potato vine can be a great ground cover in shade. The leaves are vibrant and plentiful and give a lovely tropical feel to the area. It should be noted that the sweet potato is not just a tuber growing vegetable.
The leaves make great vegetable greens and are full of goodness. The vine is a very active grower in spring and summer, so it allows continual picking if a few plants are growing.
We are fortunate where we live as the sweet potato plant grows all year, so we have an endless supply of greens if we choose to pick from the sweet potato vines growing in the shade.
Will sweet potato out-compete other plants growing in the shade?
We have found that the sweet potato vine wants to head for the light at the edges of the shade, so it can become rangy. If there are taller plants around it, the vine will climb these looking for light, and if these plants have weak stems the sweet potato can pull the over through leaf weight.
We have found this to be the case with some rosella plants that grew on the edge of the shade. The sweet potato smothered a few of them eventually.
We have ginger growing in shade alongside the sweet potato, and we find no issues between the two.
What sweet potato plant varieties will grow in shade?
There are so many varieties of sweet potato that it is impossible to say for certain which can grow in part-shade to full-shade. What we can do is share the sweet potato vine varieties we have in our yard and know to do well in all light conditions.
Purple skin with white flesh.
We don’t know the correct name of this sweet potato vine, and we have it mostly in full-sun. It will tolerate semi-shaded to full-shaded areas well with less of a tuber return.
As noted above, this plant prefers full-sun, and the leaves are not that large so relying on it for kitchen greens could be a big ask.
White skin with purple flesh.
Again, no idea of the name of this variety, but it gives great sized tubers in the right conditions. It will tolerate the same conditions as the variety above, with the notable difference in leaf shape. This variety scrambles everywhere so will give plenty of greens if leaf harvesting is desirable.
Orange skin with orange flesh.
This is our favorite sweet potato vine. It will grow anywhere and the leaves are a good size for the kitchen. We don’t know what this sweet potato vine is called either. Great help, aren’t we!
These varieties of sweet potato vine we have in our yard have been given to us over several years and the locals know them by the skin and flesh colors only.
This variety will grow anywhere and give tubers in all situations. The plant will struggle to give many tubers if in full-shade. This vine is in semi-shade most of the time with morning sunlight for 2-3 hours.
Is sweet potato beneficial to other plants in the shade?
We tend to think this is the case. The leaves help with moisture retention and the vine roots help break down the mulch allowing nutrients to be more accessible to less aggressive plants.
It is an easy task to get in the garden with a pair of snips and thin the vine out occasionally. When we do this, the chickens get a great feed of fresh leaves and any bugs that were unlucky enough to be involved.
How much sunlight does sweet potato vine need?
To get the best harvest, sweet potato needs at least 6 hours of full sun and grows best when up to ten hours sunlight is available.
The plant will grow in many different light conditions, in sun or shade, and in partial shade. We suggest you plant several areas with sweet potato slips to discover the best lighting and location in your garden for growing this vegetable.
We have several patches in our garden, and while we do plant the occasional crop in metal raised garden beds, we tend to leave the plant to its own devices, and it basically grows wild.
When we need sweet potato for the kitchen, we go out into one of these patches and have a dig around in the soil. This process allows us to see where the sweet potato plants are most productive, and we can say very confidently that a shaded sweet potato vine is less productive in tubers.
The leaves are far healthier than sun-exposed plants, meaning the shade-grown vines are more productive in greens than a sun-grown plant.
Will sweet potato vine die back if you plant it in shade?
We live in a tropical zone, and the sweet potato vine never stops growing. In colder zones, the plant will die back as it is very sensitive to cold and the growing season is often too short to harvest tubers of any significance.
The leaves are still a reliable crop if you wish to try them for this purpose. You can carry some slips over the winter in heated spaces to allow replanting when the warmer weather arrives next season.
If you plant sweet potato in shade, are all parts of sweet potato vines edible?
All parts of the sweet potato vine are able to be eaten, from the leaves and stems to the tubers. We regularly eat the leaves and stems along with other greens in our yard; to the point that we haven’t bought any green vegetables for over three years.
We are self-sufficient in green vegetables, we are excited to share, and at the prices asked at the supermarkets, more people should also become self-sufficient in greens.
If you found this article useful and you wish to know more, we suggest the following articles..
- Can you grow sweet potato in clay soil?
- Sweet potato propagation tips.
- Do sweet potato vines need mulch?
- Growing sweet potato vine from cuttings.
- A beginners guide to growing sweet potato in raised garden beds.
Summary.
Because the sweet potato vine gives limited harvests when grown in shade, it is easy to discount the potential of this plant if you have limited sunlight available to grow it. We suggest re-thinking this.
If pushing for self-sufficiency is a goal of yours, as it is ours, placing plants in shaded areas can be a good strategy worth considering, as long as there is a harvest of something from that plant.
Suppose you didn’t plant that sweet potato vine in the shade. What weed would potentially fill that spot? Why not plant edible varieties that take care of themselves.
This is the way we approach our entire garden, or permaculture system as we call it. Over time this design process delivers an easy-to-manage food production system that gives food security, food resilience, and some of the best tasting produce available.
Article by Tim Blanch for TheTropicalHomestead.com. He is a qualified Permaculture designer.
