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I planted a lavender hedge in the front garden last autumn. It's English lavender (Hidcote). Everything seemed fine and they were growing well. Then all of a sudden one plant just died. Simply went brown and kicked the bucket. I was a bit shocked as it seemed to be growing well and had doubled in size this summer.

I've now noticed another plant (at the opposite side of the garden) also starting to go brown and start to die off. Unfortunately I don't have photos to hand but one side is dying where as the other side is not. This happened to the previous plant and eventually the entire plant died off.

I'm a bit confused as to what's going on. It's a sunny part of the garden (North facing but not in shade). The soil is quite rich (loam) so I planted the lavender on a mound with plenty of grit added under the plant to prevent the root getting water logged.

I haven't particularly watered them a lot as I was wary of over watering.

Is this a moisture issue or some kind of disease/parasite? What should I do to save it?

Dead plant

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Dying(?) plant

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Soil is mounded (though this seems to of dropped since I did it). I added a good handful of potting grit under each plant to improve draining. Is this the problem then maybe?

__  |  ___ <-ground level
  \   /
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   grit
  • How high was the mound compared to the size of the original roots? Damage from drying out can take some time to appear if you don't look closely. A small lavender can easily double in size just with the flower stems; that's not necessarily a sign it's doing well. How big were they when you put them in? – Chris H Jul 20 '17 at 13:42
  • I'm not 100% sure. About the 3/4 height of the roots. They we're about 2-3" in diameter. Without the flower stems they're now 12" so they've come on well mostly –  Jul 20 '17 at 14:33
  • Please send pictures! Are you saying HALF the plant dies or that half the row dies? The red flag was when you said that you had a previous lavender plant that died and you replaced this plant with lavender. Is that right? You could easily be dealing with a disease by the sounds of what you've said. Also, did you raise the soil to be a raised bed? GOOD JOB! You intuition about water was spot on! Do you know the pH of your soil by any chance? Have you fertilized? Adding grit or sand does not help with drainage but couldn't possibly be a problem. I love Hidcote. Where do you live? – stormy Jul 20 '17 at 20:28
  • Added details @stormy –  Jul 21 '17 at 10:23
  • Hey @stormy. You should put all that into an answer! Thanks! –  Jul 24 '17 at 08:01
  • I thought I had already done an answer instead of all those comments. Grins. Do send a picture of the whole of your back yard (?). It is also nice to have extra lavenders in pots in potting soil that would be the same variety, Hidcote and the same size when one plant bites the dust. – stormy Jul 24 '17 at 18:33

1 Answers1

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I reread your question and you say you put 'grit' beneath the plant when you planted? I take back that that might not be the problem. If you've got silt loam soil (small pores) and you used 'grit' that has large pores you might have made a perched water table which actually inhibits drainage. How much did you use beneath these lavenders? What size is this grit is it sand or gravel? How thick of a layer? The deal with adding rock, grit, gravel below the soil means the smaller pores in the soil above have to become saturated before any water will start to drain into the...more porous layer. This is more prevalent in pots because some old lady started this thing with the rock layer beneath the soil to enhance drainage. It does the opposite. The soil has to be completely saturated before the water is able to slowly move down and into the rock/grit. Pretty interesting physics.

But this wouldn't be true for the lavender on the other side of the yard.

Pull up the dead plants, lets not worry about that grit right now. These plants are pretty tough and this is in the garden not a pot type situation. The plants look healthy otherwise and what I am seeing looks fairly normal for lavender. The reason this plant isn't used for hedges is exactly because parts or whole plants die for no discernible reason. What you do need to learn is how to prune these guys. After flowering at some point you need to use hedging shears and lop of all the flowers and tips of the leaves. Imagine a salad bowl upside down. Keep the shears tangent on the surface of this bowl. This should be done at least once per year. The bowl should be a wide gently sloping UPSIDE DOWN bowl. The bottom needs to be the widest point of this bowl. I like a flat bottom for the top of the shrub...ha ha ha does that make sense? Doing this will thicken and re energize lavenders. You should be able to buy one gallon plants and plant them offset, a zigzag pattern. Take the top picture, pull the dead one out and plant a new plant about 8" closer to the wall and a couple of inches away from the existing one. The next plant going to the left would be closer to the rocks in front, not in line with the original plant on the right.

This way there are no straight lines and when one dies it will not be noticeable. This is called a 'soft' hedge. Try to keep the distances consistent but always one forward, one back zigzag. Think of salad bowls touching and pruning so that you have a soft mounding mass of lavender sweeping the length. Also plant a bit of a lavender hedge of at least three elsewhere in your yard to pull this plant into your landscape. I would also incorporate an evergreen shrub to be part of a 'skeleton' planting.

This is just an idea and I hope this is somewhat clear using just words to describe...I'd use Ilex 'Sky Pencil' in a line behind the lavender. Placed very regularly in a line behind the lavender. Perhaps 3 feet apart, the line exactly 1 1/2 feet from your fence. The lavender will become this gray purple cloud at and around the base of these shiny, vertical, architectural looking dark green plants. I can't see what you've got going, wish I knew how to DRAW on this internet...if you could send a picture of your entire back yard and also a clear picture of this hedge and brick wall I could try to explain better if necessary.

stormy
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  • I dug up a dead plant. Nothing seemed saturated though it is damp. I'm thinking the Grit under the plant is the culprit. I've re-planted new plants where the dead ones we're and dug the grit into the soil instead of as a layer under the root. Let's see how that works out. Thanks –  Jul 25 '17 at 08:48