Do Lemon Trees Have Thorns?
Yes, many lemon trees have sharp thorns, especially on young, vigorous growth and on shoots produced by a grafted tree’s rootstock. A thorn does not mean the tree is unhealthy or unable to bear lemons. What matters most is where the thorny branch begins: growth below the graft union should usually be removed, while thorns on growth above it are often normal.
Use the thorn’s location, not its presence alone, to decide what to do.
| What You See | Likely Cause | What To Do |
|---|---|---|
| A few needle-like points on otherwise normal branches | Normal lemon-tree growth | Leave them alone or prune the entire branch only if it is poorly placed. |
| Long, very thorny shoots growing from the lower trunk | Rootstock growth on a grafted tree | Remove the whole shoot where it starts. |
| Half the tree has thorns and half does not | Different growth types, possibly rootstock on one side | Trace each thorny branch back to its point of origin. |
| A seed-grown lemon tree with many thorns | Juvenile citrus growth | Leave the thorns; they do not prove the tree cannot fruit. |
| Thorny shoots with noticeably different leaves or a more upright habit | Likely rootstock sucker | Remove the shoot at its base without damaging the trunk. |
Why Lemon Trees Grow Thorns
Thorns are a normal trait in citrus. They are stiff, pointed growths attached to the stem, often near the point where a leaf joins the branch. If your lemon tree seems to have grown “needles,” those are usually thorns rather than a pest, disease, or sign of poor care.
Lemon trees tend to make more noticeable thorns on vigorous new shoots. Young trees, seed-grown trees, and branches that are growing quickly can be especially thorny. As the tree matures and begins making more fruiting wood, some branches may become less thorny, but there is no guarantee that thorns will disappear.
A grafted lemon tree adds another possibility. Commercial lemon trees are commonly made from two plants joined together:
- The upper portion, called the scion, is the named lemon variety you bought.
- The lower portion, called the rootstock, supplies the roots and lower trunk.
Rootstocks can be much thornier than the lemon variety grafted onto them. If the rootstock sends up a new branch, that branch may grow quickly, carry large thorns, and eventually compete with the lemon-producing part of the tree.
The origin of a thorny branch matters more than the thorn itself.
How to Deal With Thorns on a Lemon Tree
Thorny growth below the graft union should be removed, while normal thorny branches above it can remain or be pruned for safer access.
Step 1: Trace the Thorny Branch to Its Starting Point
Put on sturdy gloves before handling thorny citrus branches. Follow the branch from its thorns back toward the trunk or main limb.
Look for the graft union near the lower trunk. It may appear as a bump, bend, seam, change in bark texture, or slightly swollen area where the upper lemon variety was joined to the rootstock.
- A branch that starts above the graft union belongs to the lemon variety.
- A branch that starts below the graft union belongs to the rootstock.
- A tree grown from seed may not have a graft union at all.
Do not decide based only on how sharp or numerous the thorns are. Some lemon-variety branches can be thorny, including branches on Meyer lemon trees.
Step 2: Remove Rootstock Shoots
If the thorny shoot starts below the graft union, remove it. Rootstock shoots will not produce the lemon variety you intended to grow, and they can eventually take energy and space from the productive canopy.
For a small, soft shoot, rub it off carefully with a gloved hand. For a woody branch, use clean, sharp hand pruners and cut it off at its point of origin without cutting into the trunk or leaving a long stub.
Remove every branch that clearly starts below the graft union, then check the lower trunk again for small shoots that may have been hidden by leaves or mulch. Finish by clearing the pruned material away from the pot or planting area.
Step 3: Leave Normal Thorns on the Lemon Variety
If the thorny branch begins above the graft union and has the same leaves and general appearance as the rest of the lemon tree, the thorns are usually normal. Do not clip off individual thorns one by one. That creates unnecessary wounds and does nothing to improve fruiting.
Instead, decide whether the entire branch deserves to stay:
- Keep a branch that is well placed, leafy, and part of the tree’s main canopy.
- Remove a branch only if it is broken, rubbing another branch, growing into a walkway, or making the tree crowded.
- Make pruning cuts at the branch’s origin or back to a healthy side branch, rather than cutting off only the thorny tip.
A thorny branch above the graft union can still flower and produce lemons.
Step 4: Make the Tree Safer To Handle
You do not need to make a lemon tree completely thorn-free. Focus on keeping thorny branches out of places where hands, faces, pets, or passersby will brush against them.
Wear gloves and long sleeves when pruning or harvesting. Move carefully through the canopy rather than reaching blindly for fruit. If a thorny branch extends into a path or patio space, prune that whole branch back to a sensible branching point rather than stripping its thorns.
When you finish, the goal is simple: rootstock growth is gone, the lemon canopy remains intact, and accessible branches are less likely to snag you during harvest.
When Half a Lemon Tree Has Thorns
A lemon tree with thorns on only one side may have rootstock growth, but that is not the only explanation. One limb can simply be younger or more vigorous than the rest of the tree, especially after pruning, damage, or uneven light.
Start by tracing the thorny side back to the trunk. If those branches all begin below the graft union, they are rootstock shoots. If they begin above the union, they are part of the lemon variety and can stay unless their position creates a problem.
Compare the foliage as well. Rootstock growth often looks different from the desired lemon canopy. It may have a different leaf shape, leaf color, branch angle, or growth habit. A sharp change in foliage and thorniness near the base of the tree can help identify a different growth type.
If you cannot find a graft union, avoid making a large cut simply because a branch has thorns.
Thorns, Flowers, and Fruit
Thorns do not stop a lemon tree from fruiting.
Thorns also do not mean the tree is “ready” to fruit. They are a growth trait, not a fruiting signal. A young lemon tree may have many thorns before it produces fruit, while a mature tree may have few thorns and still be productive.
This distinction is especially useful with Meyer lemons. Improved Meyer lemons are a hybrid type believed to be related to both lemon and mandarin, but thorniness is not a reliable way to identify one. A Meyer lemon can have some thorns, and a grafted Meyer may also produce very thorny rootstock shoots below the graft union.
If your tree has lots of thorns and no fruit, first determine whether the thorny growth is rootstock. For growth above the graft union, focus on overall tree health. Lemon trees need full all-day sun, regular deep watering, well-aerated soil, and good airflow to grow well, as outlined by Four Winds Growers.
Keep Rootstock Growth From Returning
Rootstock shoots can reappear, particularly from the lower trunk or near the soil line. Catching them while they are small is easier than allowing them to become thick, thorny branches.
Keep the graft union visible rather than burying it under soil or a heavy layer of mulch. That makes it easier to see which shoots belong to the rootstock and which belong to the lemon variety.
When you inspect the tree, make sure the main canopy is made up of branches from the desired lemon variety.
A healthy lemon tree does not need to be thornless. A healthy lemon tree needs to be growing from the right part of the tree.
Frequently Asked Questions
Why Did My Lemon Tree Grow Thorns?
Lemon trees naturally grow thorns, especially on young or vigorous shoots. A sudden flush of thorny growth may simply be new growth, but shoots that begin below the graft union are usually rootstock growth and should be removed at their origin.
Are Lemon Tree Thorns Harmful to Humans?
Lemon tree thorns can scratch or puncture skin, especially when you reach into a dense canopy to prune or harvest. Wear gloves and long sleeves, and work slowly so thorny branches do not spring back toward you.
Do Lime Trees Have Thorns?
Yes, many lime trees and other citrus trees can have thorns. The same rule applies: thorns on normal branches are often harmless, while thorny shoots growing below a graft union should be removed because they are likely rootstock growth.
Should I Cut the Thorns Off a Lemon Tree?
No, do not remove individual thorns just to make the tree look smoother. Remove the entire shoot only when it is rootstock growth, damaged, crowded, or growing where it creates a safety problem.
Can a lemon tree with lots of thorns still produce fruit?
Yes, a lemon tree can produce fruit even when many of its branches have thorns. A documented dwarf Meyer lemon had tiny fruit on branches that were mostly thorny. However, thorny branches growing below the graft union will not produce Meyer lemons and should be removed.
Are hybrid lemon trees thornless?
Hybrid lemons are described as lacking the sharp thorns associated with true lemons. A grafted Meyer lemon can still have thorny branches from its rootstock, so remove any that start below the graft union because they will not produce Meyer lemons.