How to prune salvias?

Salvia leucantha “Santa Barbara.” It has a compact growth habit & the flowers are a rich purple.

Salvias are popular all the world over and are so versatile because they can comfortably fit into many styles of gardens from old fashioned cottage right up to modern simplistic.

They grow well here in California where our Mediterranean climate suits them to a tee and they’re loved because of their long bloom time. It’s an added bonus that their nonthirsty ways are so appropriate for the water starved western US.

I first learned all about perennial salvias in the San Francisco Bay Area where I was a professional gardener for over 15 years. The nursery where I worked in Berkeley sold many different species and varieties of them.

This post is all about sharing what I know about pruning (this is the big cut back, not the dead heading you do throughout the season) the two most popular types of perennial salvias which you probably have in your own garden.

Plus, I also mention a 3rd type which you may not be familiar with.

I did a post on pruning perennial salvias a few years ago but the video that went with it was under 2 minutes long. Time for an update with much more detail. I filmed this longer video in my client’s garden in Pacifica, CA (just south of SF) in early December:

I’ll be talking about pruning salvias here in coastal California. You can tweak the process for your climate zone if they’re perennials where you live. There’s a long standing debate of sorts about giving salvias their big pruning in fall vs spring. It’s simply a matter of preference. I go back and forth on this topic but these days am more a proponent of fall/winter pruning. I sometimes find it necessary to do a light “clean up” pruning in early spring too.

We have lots of year round interest in our gardens so that’s why I prefer to do it in mid to late fall. This way the plant looks better over the winter months and growth is nice and fresh earlier on in spring. If you’re in a colder climate, just make sure to prune in the a fall well before the threat of frost and after the last chance of it has passed in spring.

Salvia elegans, or Pineapple Sage.

#1 The Deciduous Herbaceous Salvias.

This category includes: Salvia elegans, S. guaranitica, S. leucantha, S. waverley, S. ulignosa & S. patens.

With these salvias the old growth eventually dies out and the fresh new growth emerges from the base of the base. They have softer stems which either die off and/or freeze. These types of salvias are better to prune in spring (in colder climates) because the old growth will protect the fleshy new growth over the winter. In the video you see me working on a Salvia leucantha (Mexican Bush Sage), Salvia elegans (Pineapple Sage) and Salvia Waverley which I just talk about. These salvias are very simple to prune.

When they’re through flowering, simply cut those stems all the way down to the ground. It needs to be done once or twice a year. They will still flower if you don’t but you’ll get more blooms and the plant will look 100% better if you do. Here in Santa Barbara the leucanthas and the waverleys get huge. Many of them are not cut back leaving a tangle of dead twisted stems and they look like a ratty mess. I want to prune them all back but don’t want to get arrested for trespassing!

So, it’s best to give them the shearing back they need because this lets in the light and air they need to regrow. That allows the soft new growth to appear at the base. Another thing to know is that these salvias tend to spread as they grow so you might have to do a bit of dividing.

Salvia microphylla “Hot Lips”.

#2 The Herbaceous Salvias With Woody Stems.

This category includes: Salvia greggii (there are so many of these!), S. chamaedryoides, S. coccinea and S. microphylla (there are quite a few microphyllas too). These are the shrubby salvias.

You prune these salvias back after flowering but not all the way. Take them back to at least where the first set of foliage starts on the flower stem – this could be a pinch or you can take them down further if they need it. I learned the hard way on an established plant to not cut it down to 3″. It never fully came back and out it came.

With these types of salvias I thin out what I want in the middle and then shape the plant so it’s pleasing to the eye. They usually go through 3 bloom cycles throughout the year here. We have a long growing season. I give them their “more intense” pruning in late fall or early winter and lighter ones in late spring and mid summer.

Be sure to take out any growth which has died over the winter. If you don’t give these salvias some type of pruning they will get extremely woody and won’t repeat bloom like you want them to. Plus, they get straggly and sparse – not a pretty sight in the garden.

In my years of working with salvias I found that some needed to be replaced before or around the 5 year mark. This is especially true with this type. Perennials don’t live forever after all. No worries though because they grow fast, especially if you purchase a 1 gallon plant.

Salvia nemorosa “May Night”.

#3 The Rosette Forming Herbaceous Salvias

This category includes: Salvia nemorosa, S. x superba & S. penstemonoides.

These salvias form low rosettes (which are evergreen here) and the stems with more foliage and the flowers emerge out of them. The 1 that you see me pruning in the video is Salvia nemorosa (Meadow or Woodland Sage) and I’ve found that this has a very long bloom time.

I prune the stems all the way down to the rosette and also clean up any dead foliage growing close to the ground. The leaves tend to grow densely on this 1 so the undergrowth gets smothered.

Bottom line: It’s best to know which kind of salvia you have before springing into action with the pruners. All 3 types of perennial salvias really benefit from a good haircut. You’ll get much better flowering and shape if you do so. Whether you prune in fall or spring is up to you. Just keep those salvia blooms coming please – the hummingbirds and butterflies agree!

Happy Gardening!

How to grow salvias

The Salvia genus is vast and includes around 900 species. The range of different salvias available to gardeners is huge with flower colours from electric blue, bright red and lemon yellow can be selected.

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Flowers are tubular with a split lower petal. Foliage shapes and colours are also very varied and often scented when crushed. Choose between annuals often used for bedding schemes, hardy herbaceous salvias or woody tender types. The herb sage is a salvia and has many culinary uses.

More on growing salvias:

  • 20 spectacular salvias to grow
  • What to grow with salvias

All of them enjoy a sunny spot and are attractive to both bees and butterflies. Salvias are highly praised for lasting flowers from mid-summer to autumn.

Salvias are ideal for a coastal garden and are often a key plant in a drought garden.

Where to plant salvias

Salvia coccinea ‘Hummingbird Mixed’

All salvias enjoy a position of full sun. A south-facing aspect is ideal. They can cope in quite poor soils – in fact they prefer this to an unworked heavy clay.

Salvias are ideal for a coastal garden and are often a key plant in a drought garden.

Salvias of all types can be grown in containers. Some of the very long-flowering types such as Salvia greggii can be moved from the garden into the conservatory as flowers will continue into winter. Add horticultural grit to improve drainage and feed container-grown plants in spring. Plants grown in a garden soil don’t need feeding.

How to plant salvias

Salvia ‘Mulberry Jam’

Add horticultural grit to a heavy soil before planting. Avoid planting these sun lovers too close to overhanging trees.

Salvias look spectacular when planted in a group. These wonderfully coloured flowering plants look at home in a tropical garden.

If growing tender types it may be easier to grow them in containers so they can be easily moved to a frost-free place before autumn frosts.

Propagating salvias

Taking salvia leaf cuttings

Salvia cuttings can be taken in April, August or September. Remove non-flowering stems that are about 8cm long. Remove the lower leaves and trim each cutting just below a node. Insert cuttings into a pot of pre-watered cutting compost. Cover the pot with a clear plastic bag – try to avoid the bag touching the foliage.

Place cuttings in a cool greenhouse and put up shading to prevent scorching from strong sunlight. After three weeks cuttings should be ready to pot on.

Savlias: problem solving

Salvia patens ‘Cambridge Blue’

Pests and diseases are rarely an issue for salvia growers. However, keeping plants through the winter can be tricky. Gardeners that have heavy clay soil are likely to lose plants in persistent wet weather.

It’s worth remembering that salvias are Mediterranean plants and require a well-drained soil and full sun.

Looking after salvias

Cutting back salvias in autumn

The care of salvias varies tremendously depending on the type you grow. 
If growing annual types they’re simply lifted from a display before the first autumn frost and put on the compost heap.

Hardy perennial types can be cut back hard in spring or autumn. Half-hardy herbaceous types can be cut back in autumn but must then spend winter in a frost-free place. If you’re attempting to keep them outside resist pruning until spring. Shrubby types should be lightly pruned in spring – prune these in autumn and new growth will form that can be hit by frost.

If you’re not sure what salvia you are growing then leave pruning until spring. This will offer them some protection over winter.

Grow your own sage

Dried sage is often found for sale in the supermarket but fresh sage is seldom seen. Grow your own to enjoy a more vibrant taste. Sage and onion stuffing will taste so much better with fresh, home-grown sage.

Salvia nemorosa ‘Caradonna’

Great salvias to grow

  • Salvia officinalis – the common sage has many culinary uses. Variegated forms are available. Evergreen, shrubby plant with scented foliage and blue summer flowers. Reaches a height of 75cm
  • Salvia nemorosa ‘Caradonna’ (pictured) – a hardy perennial with spires of electric blue flowers in July to early September. Reaches a height of 50cm
  • Salvia greggii ‘Stormy Pink – soft pink flowers from July to November. Aromatic foliage. Reaches a height of 65cm. Semi-hardy plant that may survive in a very sheltered garden
  • Salvia involucrata ‘Bethellii’ – a half hardy salvia with large purple/pink flowers from August to late autumn. Unlikely to survive winter outside. Reaches an impressive height of 1.5m
  • Salvia farinacea ‘Victoria’ – a half-hardy perennial that is more often grown as an annual. Electric blue flowers from June to October. Plants reach 40cm
  • Salvia nemorosa ‘Ostfriesland’– a hardy perennial which is extremely popular with pollinators. Tall spikes of purple flowers from June to September. Plants reach 75cm
  • Salvia ‘Amistad’ – a half-hardy perennial. Long-flowering and particularly floriferous with rich-purple flowers. Often still blooming when first frosts arrive, and a good food source for late-season pollinators. Plants reach 1.2m

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Browse more great varieties to grow here

They grow to around 2ft high but have a delicate canopy of small, glossy green oval leaves that perfectly sets off the brilliant flowers. Look out for any varities of Salvia greggii and beauties like ‘Mr Bumble’ which is bright red.

What makes them really attractive is the ease with which they can be propagated. Shoot tips 3in long can be stripped of their lower leaves and pushed into pots of sandy compost any time now. Pot up the youngsters once they are well rooted, and overwinter them in a cool greenhouse or porch as an insurance policy against the loss of those that remain in the garden.

Those that do stay outside may well take a bit of a battering over the winter, but don’t be tempted to cut them back until spring, when you can snip back the old stems to just above an emerging shoot 6in or so above soil level. Soon they will have furnished themselves with new leaves and an array of flowers and be none the worse for their winter ordeal.

Accompanied by silver-foliage plants such as artemisia, and mixed with diascias and penstemons, you will find that any sun-drenched spot can be turned into a hugely colourful feature that can be fitted into the smallest of gardens. The fact that the plants keep flowering right until the frosts of autumn makes them tremendously good value. I wouldn’t be without them.

Don’t miss Alan’s gardening column today and every day in the Daily Express. For more information on his range of gardening products, visit alantitchmarsh.com.

Perennial salvias need to be deadheaded

Question: Am I supposed to deadhead or prune ‘Merleau Blue’ salvia• If yes, where on the flowering portion do I cut?

Answer: You should deadhead all perennial salvias, including ‘Merleau Blue,’ to promote more flower production. Just follow each flowering stem from the top down to the first branching point where new buds should be forming. Cut the stem off just above the branching point. I deadhead my salvias three or four times during the growing season, and they bloom from June through September.

Question: We just had a bunch of deer-eaten yews taken out from in front of our house. Now we need to plant something else there and I need it to be something Bambi doesn’t like (at least not as much as he liked the yews!). I’d like it to be evergreen. Flowers would be nice, but my heart isn’t set on them. I just want something that will look decent year-round. Help!

Answer: While there are some evergreen shrubs that are less prone to deer browse, no plant is 100 percent deer-proof. Plan to cover your shrubs each winter with black plastic deer netting (available at local garden centers) and spray them with deer repellant every week or two during the growing season (my personal favorites are Plantskydd and Tree Guard brands). The deer clearly have a feeding habit established at your place and you have to work to break them of it by being religious about protecting your plants.

Here are the shrubs I would recommend you plant: Boxwood, Pieris japonica, Andromeda, Cotoneaster, bird’s nest spruce, junipers or Mugo pines are your best bets. The Pieris and Andromeda are the only ones with noticeable flowers, but the rest are beautiful without them. All these plants are regulars at your local garden center so finding them shouldn’t be too difficult. Buy healthy potted or balled-and-burlapped specimens and plant them in early September. Keep your new shrubs well watered through the winter and all of next season.

Horticulturist Jessica Walliser, co-author of the book “Grow Organic,” can be heard from 7-8 a.m. Sundays on KDKA Radio’s “The Organic Gardeners.” You can also find her teaching at Phipps Conservatory and Botanical Gardens, where she has been a faculty member for more than 12 years.

Send your gardening or landscaping questions to [email protected] or The Good Earth, Tribune-Review 503 Martindale St., 3rd Floor, D.L. Clark Building, Pittsburgh, PA 15212

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    Salvia is a very well-known genus of plants. Its most famous member, sage, or Salvia officinalis, is grown as a spice and medical herb. However, we are often forgetting another salvia, Salvia nemorosa, which is as useful to your garden as sage is for your body … or maybe even more… Here are some reasons why we should be growing salvia in our gardens!

    1. Salvia flowers for a very long time and once it’s done flowering, you cut the old flowers down and it will flower again!
    2. There are dozens of different salvia colors and shades. From white through pink to very dark blue. Even when the plant loses its petals, the spikes of blue salvia stay very decorative, as they keep a blue tinge which adds color to the flower bed.
    3. A salvia plant has a compact, stiff structure that does not require support to resist even strong winds. Salvia flowers look great also after strong rains and in cold weather.
    4. Salvia is one of the best bee friendly perennials.
    5. There are plenty of hardy salvias to choose from. Even if you live in the North you can make very decorative flower beds with the help of this plant.
    6. Salvia is one of the best companion plants for roses, peonies, large daisies and basically all other plants in your garden.
    7. It is very easy growing salvia. You need to simply deadhead salvia twice a year and that’s basically it!

    Are you convinced that salvia is a great flower for your garden? Now let’s dig deeper into the beautiful world of salvias.

    Salvia varieties

    Here come the salvia varieties that we are growing (or tried growing) in our garden. All the observations and advice reported below are based on our experience with these salvias.

    East Friesland Salvia

    This is a great blue salvia variety. Salvia East Friesland (or to be correct Salvia nemorosa “Ostfriesland”) is a very decorative and hardy plant that survives even on our North facing slope.

    Blue Queen Salvia

    Salvia Blue Queen (also known as Salvia nemorosa “Blauköningin”) is very similar to the East Friesland variety. It is as hardy and as decorative as the former, and to be fully honest I cannot really distinguish these two varieties. They are equally great and recommended!

    East Friesland Salvia, yellow Alchemilla mollis and the gray-lilac Nepeta racemosa (out of bloom) Blue Salvia nemorosa, yellow Alchemilla mollis and the lavender Nepeta racemosa (out of bloom) Crown Princess Margareta surrounded by Salvia nemorosa, 27.07.17

    Snow Hill Salvia

    This is a white flowering salvia variety. Salvia Snow Hill, or Salvia x sylvestris “Schneehügel”, is a great addition to any garden. It flowers prolifically, it grows well and it is one of the best hardy salvias on the market. In our garden it was growing so well that it was taking all the space that was reserved for ground covering plants. For this reason, we decided to move the plant to another spot where it would have more space, and dug it out. Snow Hill was so strong that it started growing back from a piece of root that we had accidentally left in the ground. A truly tough plant!

    I see only a minor disadvantage in this plant, compared to the blue salvias. Snow Hill salvia is not as decorative as Blue Queen and East Friesland after their petals have fallen. This is because the colour of the blue salvia’s spikes is purple, while the spikes of Snow Hill are green. This makes the latter blend with the surrounding green foliage. However, the white salvia flowers for a very prolonged time period, especially if pruned, so the time when it is decorative will outlast the times when it is not.

    Snow hill salvia and roses Notice the two Salvia nemorosa plants over the bench. Although planted at the same time, it is almost impossible to see the pink salvia, while the white one is very large and visible. 24.07.15
    Snow Hill salvia, pink dianthus, Abraham Darby rose and blue delphinium. 27.07.17 Snow hill salvia and flowers of Abraham Darby after the rain. 24.07.15 Salvia snow hill and rose Abraham Darby

    Sensation Rose Salvia

    This pink salvia was not hardy enough for our Nordic garden. Salvia nemorosa “Sensation Rose” became weaker and weaker each new season, and one spring, it just did not wakeup. It was planted at the same time as the Snow Hill salvia, and in the picture below you can see how much smaller Sensation Rose looked compared to its white neighbour already one year after planting. I definitely do not recommend this pink salvia variety for gardens with cold winters.

    Notice the two Salvia nemorosa plants over the bench. Although planted at the same time, it is almost impossible to see the pink salvia, while the white one is very large and visible. 24.07.15

    Where to plant salvia

    Salvia thrives the most in full sun. However, over the years we have planted salvia in most environments. We have tried in full sun, half day sun, on slopes facing north (the blue salvias do great there) and in shady spots. We had some blue salvias planted in dry half shade and some in moist shade. Although both perennials survived, the ones in moist shade are doing much better.
    The bottom line is that salvias are very tough and hardy plants and will survive in most spots. Just remember to give them a good feed and soak, if they are planted in a dry shady region.

    Caring for salvia

    Salvia is a perennial, which means each autumn the part above the ground will die, and in spring the plant will start growing again from the root. Caring for this plant reduces itself to one main activity: pruning salvias when their spikes have lost most of their petals. You will need to do this activity at least once, in summer, after the first rush of flowers, to prolong the flowering time of salvia. It does not have to be accurate, cut the whole plant just below the end of most flowering spikes. However, if you take your time and go trim each spike separately, you might save some new spikes that are arising. This means your salvia will start flowering again faster. However, this meticulousness is not really necessary.

    Pruning salvias is quite a tragic procedure for me. Firstly, you deadhead the plant while there are still few flowers on it, which are constantly visited by pollinators. It is very sad having to deprive bees of their food. Secondly, the spent spikes of blue salvia look very pretty, therefore it is sad to deprive the garden of this decoration. Thirdly, when pruning salvias, the plants starts smelling like cat urine. This is not very pleasant, but due to its beauty, I can forgive salvia this minor drawback : )

    If you do not like how the spent spikes look, you can deadhead salvia once more after its second flowering. We like how the spikes of our blue salvias look like after flowering, as they add beauty to the autumn garden. However, we trim our Snow Hill Salvia after it has finished flowering to keep this perennial compact.

    The last time you will need to use your shears on salvia is in late autumn, this time by pruning salvias to the ground.

    Attract pollinators with salvia

    Salvia is one of the best bee friendly perennials you can get. Not only does it attract lots of different bee species, but the various salvia colors attract different species of pollinators. Our research shows that blue salvia attracts Bombus lucorum (white-tailed bumblebee) and Bombus pascuorum (common carder bee), while the white Salvia is visited exclusively by Bombus lapidarius (red-tailed bumblebee). Not many pollinators were interested in the pink Salvia.

    Garden design with salvia

    Salvia looks best when planted between other plans or shrubs.

    It is one of the best companion plants for roses and there are so many salvia colors to match all the rose tonalities! White salvia goes well with red and pink roses. Blue salvia looks great with apricot coloured, pink, white, red and many other roses.

    Besides roses, salvia is the best companion plant for many perennials. Plant salvia next to nepeta, dianthus, alchemilla, aquilegia and many more to get a beautiful flowerbed that will be decorative for the whole summer.

    My favourite composition is planting blue salvia together with Nepeta racemosa and Alchemilla mollis (see the pictures below). These three plants can be planted in a flowerbed, or even better next to a pathway, repeating several times the sequence (Salvia, Nepeta, Alchemilla, Salvia, Nepeta, Alchemilla, …). This is an easy, but stunning arrangement that will immediately increase the beauty of your garden.

    East Friesland Salvia, yellow Alchemilla mollis and the gray-lilac Nepeta racemosa (out of bloom) Blue Salvia nemorosa, yellow Alchemilla mollis and the lavender Nepeta racemosa (out of bloom)

    Conclusion

    East Friesland, Blue Queen and Snow Hill Salvia are the best perennial salvias we grow. I strongly recommend growing salvia to everybody, newbies and experts alike. I gladly give the Amberway Approval to the blue and white salvias!

    Plant Details:

    Flowering time: Summer and Autumn

    Spreading: Middle-High

    Flower yield: High

    Sun exposure: ¼ to ¾ day sun

    Scent: No

    Pollinator attraction: High

    Lowest temperature survived: -24°C

    You may not want to bother removing the flower-bearing stems on many types of salvia that are grown for hummingbirds.

    These stems simply dry up by themselves and since our annual salvias generally do not produce seeds in great number; this need not be a concern for you. Salvia coccinea does produce seeds on these stems. Some gardeners recommend that flower stems should be removed from plants once the flowers stop looking attractive in order to prevent the plants from producing seeds, which can reduce future blooming. This does not happen with salvia coccinea, which produces both lots of seed and lots of flowers all year long. Once any part of a plant turns brown and brittle it may be removed without harming the plant, since brown and brittle indicates a dead part of the plant.
    If you want to promote branching in salvias, you can cut off the tip of each stem, which will usually result in two new stem tips being produced from the axils of the last pair of leaves left on the plant. When growing fall blooming salvias you can cut or pinch back the stem tips regularly until about the end of June, then stop cutting to allow the plants to produce flowers. It is necessary to remove only the growing tip of the stem to encourage branching, try to cut back after a few inches of growth has occurred to encourage the maximum number of branches. Try not to remove more than an inch or so of the stem, but if your salvias have gotten too tall you might remove much more than an inch to prevent them from becoming weak-stemmed and falling. This type of cutting back is good for salvia elegans, s. mexicama, s. iodantha, s. madrensis, s. involucrata, s. puberula, s. slendens ‘van houtte’, s. leucantha, s. purpurea, s. gesneriflorae, and perhaps other varieties. Cutting back isn’t usually necessary for salvias that bloom all summer, because cutting back would delay flowering. Once salvias flower, they generally branch out below the old flower stem automatically, so a species like s. guaranitica doesn’t need to be cut back. Some like to tidy their salvias and clip off the spent flowers, this is your choice but not really necessary.
    Each salvia variety can have its own set of pruning instructions. Some need hand pruning to each stem, while others can just be clipped-off, and still others can be sheared. Learning from experience what is best for your salvia varieties is sometimes the best way to achieve the look you want. Gardening is an art of trial and error or trial and success.
    General rules can apply to pruning salvias:
    Woody stems are pruned down to the lower set of new leaves — ex. greggii. Softer, brittle stems are pruned to the ground (or new growth if it’s started already) — ex. leucantha
    Where the leaves are basal (low to the ground in a circle) you only clean away dead leaves and remove any old stems.
    Shrubby, but not woody salvias are pruned rather short — down to lower new leaves — ex. microphillia, involucrata, elegans, “Black & Blue.”
    Note from a PCMG member: I have Black & Blue salvia guaranitica and where I have it, it must be very happy because I have to prune it hard a couple of times during the summer just so we can walk by it. I usually cut the spent blooms away to keep it flowering all season. It grows so vigorously that I have to dig some of the roots up every year just to keep it confined.
    My Victoria blue salvia is beautiful what about pruning or taking cuttings from it?
    Wait until you see new growth. Use the “asparagus” rule to trim salvias. Bending the stem until it snaps (towards the outer end) will reveal the approximate area where the transition of the woody growth to new green growth is. This is also the point where cuttings are taken.
    Treat shrubby woody-stemmed sages like greggii and microphyllas that form twiggy, woody growth like roses. Definitely do not cut these to the ground.
    Cutting to the ground is only good for those salvias that form short stolons underground and send up new shoots, like leucantha, some microphyllas, guaranitica, and others. If the plant was rooted and set into the ground with no nodes beneath the soil line, it will not send up shoots in any case. You can often tell this has happened when there is a thick trunk coming from the soil, and the first node has a multitude of stems coming from it. Cut that off, and you have a dead plant.
    Questions about cutting back salvia greggii:
    Re-blooming salvias, such as salvia greggii should be pruned back periodically during the summer. To make the job easier, use hedging shears, and remove only the spent flowers and a few inches of stem below.
    Note from Parker Master Gardener: In Parker County, salvia greggii needs to be cut back to look better, mine gets rangy looking and the wood gets brittle and does not bloom as well. Plus pruning in February will make it thicker and healthier looking in the spring. I suppose you could just leave the salvia greggii alone but mine does better cut back by one third every February.

    Cutting back Salvias

    Lambley Nursery gets lots of questions from customers about cutting back plants to get the best out of them. It is hard to generalise as we treat different plants in different ways. Take Salvias for example.

    1) The Salvia nemorosa/superba/sylvestris complex is one of the most important groups of plants in my garden both in the mixed plantings in the dry garden and the mass planting in Molly’s Garden. These herbaceous Salvias are cut to the ground and I mean right to the ground twice a year, once in early May (mid autumn) and again in late December (mid-summer).

    All of our Salvia nemorosa drifts are under planted with bulbs. We have to get the Salvias cut back and cleaned up and any remulching done early as the bulbs start to put their noses out of the ground by mid-May (late autumn). If the Salvias are not cut back by then we are likely to damage the bulbs either by trampling on them or by cutting the emerging foliage. We cut the Salvia nemorosa varieties right to the ground again just after Christmas even though they still have lots of flowers on them and still look fine. If we delay this cutting back to say mid January (mid summer) then we are less likely to get a good second flowering during late summer and autumn. A couple of varieties don’t respond so well to this second cut back; that is they don’t rebloom well. They are Salvia x superb ‘Superba’, which I first saw shining in the Sissinghurst Castle gardens, and Salvia ‘Lye End’ which was raised by Miss Poole who gardened at Lye End and is most renowned for raising Achillea ‘Coronation Gold’. Treating this group of Salvias in this way means we have them flowering for twenty weeks in a gardening year.

    2) We treat the shrubby and twiggy Salvia greggii/microphylla and closely associated species and hybrids quite differently. At Lambley these are pruned or, more accurately, clipped during late autumn and early winter. We use hedge shears to do this and just cut about a third of the growth off making a ball like shape. This shape gives some architectural interest during winter. Growth soon recommences in spring and flowering is well underway by Christmas.

    3) Salvia leucantha and its hybrids and Salvia mexicana clones flower with us until the first frosts. We then cut them to the ground and generally mulch them to protect the roots over winter. As we get late frosts here right into November (late spring) regrowth doesn’t really get going until early summer. These plants flower for us only during February, March and April (late summer-autumn) whilst in warmer areas they flower nearly the whole year round. Even if they are still in flower for you during late winter it is probably as well to cut them to the ground so that you get a fresh start each year as all the old daggy stems are removed.

    4) Salvia ‘Celestial Blue’ ‘Allen Chittering’ ‘Bee’s Bliss’ are all hybrids or selections of Salvia clevelandii. They are evergreen or rather ever-grey shrubs grown as much for foliage effect as for their whorls of lovely mauve-blue flowers. We don’t prune this group in winter as they flower on the previous season’s wood so winter pruning would seriously effect flowering. We do tidy them up when blooming is finished but this doesn’t entail any drastic pruning just cutting off errant growth and spent flowering stems. The dramatic grey foliaged shrub, Salvia apiana, with its 150cm tall flower stems is treated similarly.

    I’ll be talking about pruning salvias here in coastal California. You can tweak the process for your climate zone if they’re perennials where you live. There’s a long standing debate of sorts about giving salvias their big pruning in fall vs spring. It’s simply a matter of preference. I go back and forth on this topic but these days am more a proponent of fall/winter pruning. I sometimes find it necessary to do a light “clean up” pruning in early spring too.

    We have lots of year round interest in our gardens so that’s why I prefer to do it in mid to late fall. This way the plant looks better over the winter months and growth is nice and fresh earlier on in spring. If you’re in a colder climate, just make sure to prune in the a fall well before the threat of frost and after the last chance of it has passed in spring.

    #1 The Deciduous Herbaceous Salvias.
    This category includes: Salvia elegans, S. guaranitica, S. leucantha, S. waverley, S. ulignosa & S. patens. With these salvias the old growth eventually dies out and the fresh new growth emerges from the base of the base. They have softer stems which either die off and/or freeze. These types of salvias are better to prune in spring (in colder climates) because the old growth will protect the fleshy new growth over the winter. In the video you see me working on a Salvia leucantha (Mexican Bush Sage), Salvia elegans (Pineapple Sage) and Salvia Waverley which I just talk about. These salvias are very simple to prune. When they’re through flowering, simply cut those stems all the way down to the ground. It needs to be done once or twice a year. They will still flower if you don’t but you’ll get more blooms and the plant will look 100% better if you do. Here in Santa Barbara the leucanthas and the waverleys get huge. Many of them are not cut back leaving a tangle of dead twisted stems and they look like a ratty mess. I want to prune them all back but don’t want to get arrested for trespassing! So, it’s best to give them the shearing back they need because this lets in the light and air they need to regrow. That allows the soft new growth to appear at the base. Another thing to know is that these salvias tend to spread as they grow so you might have to do a bit of dividing.

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