Quote from Lee Garden Ninja on 17th March 2025, 12:54 pm

Hi @lucylou

Unfortunately the photo isnt attached so if you could add one that would be really helpful! However, I can give you some advice with dying or yellowing Prunus Lusitanica otherwise known as Portuguese Laurel.

I know you've said you've been watering them well, but 2m tall bare roots need a LOT of water. As they're really established plants. We're talking a full bucket each once or twice a week until they establish or use a seep hose.

What you will also find is that stronger plants will rob water from the others, in particular, if their roots are better established. Hence, you can find one of two in the middle of a row that has effectively dried out whilst their neighbours thrive. I would need to see a picture; the other causes could be lack of nutrition, especially if planted in really poor soil or in a newly built environment. 

If you want to check if they are dead, take a pair of secateurs and scrape the bark; if it's brown and crispy underneath, it is dead; if it's green and fleshy, it's still alive, so it MAY return, though in my experience, it slow and patchy trying to get them to recover.

Ideally, with such large root balls, you need a seep hose on trickle twice a week for the first year or so.

https://youtu.be/81muXEWDe9I

Can Portuguese Laurels Regrow Lost Leaves?

Yes, Portuguese Laurel can regrow leaves after shedding them, but the recovery depends on the cause of leaf loss and the plant's overall health. Since Portuguese Laurel is an evergreen, it naturally retains most of its foliage year-round, so sudden or excessive leaf drop often signals stress.

A) Mild Stress (e.g., drought, nutrient deficiency, light frost): The plant should recover within a few months, especially with improved care. New leaves will typically emerge from leaf nodes on the stems during the next growing season (spring or early summer).

B) Severe Stress (e.g., root rot, transplant shock, or extreme frost damage): Recovery may take longer. If branches are still alive, they can push out new growth — but this may only happen in spring when conditions improve.

C) Dead Wood: If a branch is completely dead (dry, brittle, or blackened), it will not regrow leaves. In this case, pruning the dead section is essential to encourage healthy growth elsewhere.

Now for all the other potential causes of a portugese laurel losing its leaves or yellowing. Let me break down the common causes and solutions for all the other Garden Ninjas to get your Portuguese Laurel back in top form.

1. Water Stress on Portuguese Laurel – Too Much or Too Little

Portuguese Laurel is drought-tolerant once established, but in its early years or during extreme weather, water stress can trigger yellowing leaves or leaf drop.

Signs of Underwatering:

• Leaves turning dry, crispy, and yellow.
• Drooping or curling foliage.

Solution: Water deeply and consistently during dry spells, especially in the first two years. A thorough soak once a week is better than frequent light watering.

Signs of Overwatering (More Common in the UK):

• Leaves turning yellow with brown tips.
• Soil feeling constantly soggy or waterlogged.

Solution: Improve drainage by aerating the soil or adding organic matter. Avoid watering unless the top layer of soil feels dry.

2. Poor Drainage or Root Rot

Portuguese Laurel dislikes heavy, compacted, or waterlogged soils. Excessive moisture suffocates the roots, causing leaves to yellow and fall.

Solution: If your soil retains too much water, consider improving drainage by adding grit, sand, or organic matter. Raised beds can also help in persistently damp areas.

3. Nutrient Deficiency

Yellowing leaves — particularly those on the lower branches — may indicate a lack of key plant nutrients like nitrogen or iron.

Solution: Apply a balanced fertilizer in spring to boost nutrient levels. For iron deficiency (common in chalky soils), use a targeted sequestered iron feed to restore rich green foliage.

https://youtu.be/5BhGtCjT2TQ

4. Frost Damage

While Portuguese Laurel is generally hardy, sudden cold snaps or prolonged frost can shock the plant, causing leaves to turn yellow or drop. Young plants are particularly vulnerable.

Solution: Protect newly planted laurels with fleece during severe frosts. Established plants will usually bounce back once temperatures rise.

5. Pests and Diseases

Although Portuguese Laurel is generally pest-resistant, certain problems can cause yellowing leaves:

• Vine weevil larvae attack the roots, leading to weak growth and leaf drop.
• Scale insects or aphids can weaken the plant, causing leaves to discolour.

Solution: Inspect the undersides of leaves for pests. Use a natural insecticide or introduce beneficial insects like ladybirds for organic pest control.

6. Environmental Stress

Sudden environmental changes — such as transplant shock, exposure to strong winds, or damage from pruning at the wrong time — can cause temporary yellowing or leaf drop.

Solution: If you’ve recently planted or pruned your laurel, ensure it’s well-watered and apply mulch to help the roots settle. Avoid hard pruning in late autumn or winter.

As for what to do if you need to replace them, you should be able to just plop new ones back in the hole unless you find out its some form of soil-borne root rot or vector, but you'll easily spot that as when you lift one it will smell eggy and the roots will be all gooey and rancid!

Do add some pictures, Lucy, and let us know how you get on.

Lee Garden Ninja