Yucca Plant - UK Cold Hardy and Colourful
The Yucca is a plant that has distinctive strap or sword like leaves, you have probably seen Yucca elephantipes (Spineless Yucca) in garden centres being sold as a houseplant. You may have also seen the tall flower spikes of Yucca Gloriosa (Spanish Dagger) in peoples gardens, this is the most commonly grown outdoor Yucca in the UK.
There are many types of palm bearing palmate leaves and palm like trunks that happily grow across most of the UK and many will easily survive temperatures well below what we experience in Britain.
Y. elephantipes is a great indoor plant and commonly available. It's a shame it isn't more frost hardy as it would make a spectacular Yucca tree if grown outdoors. However it is unlikely to survive growing outside year round over most of the UK.
The RHS gives this plant a hardiness rating of H2 which means it cannot take temperatures below freezing. I like to experiment and over the years have created a cold hardy tropical evergreen garden meaning I only grow plants that can survive outside year round and remain green.
Over the last few years I have grown Yucca elephantipes outside to see how hardy they actually are. So far it has seen two winters with minimum temperatures down to -5°C1 overnight and several days of sub zero temperatures. So far it has survived suffering only leaf damage to some of the leaves.
I have a variegated form of Y.Elephantipe which has proved to be hardy for me over the last 4 winters, probably seen at least -5 in that time, and as you know variegated anything is usually less hardy.
Hardy Tropicals Forum2
If you wanted to grow a Spineless Yucca outside in a pot and bring it inside in the UK then you shouldn't have any problems. I wouldn't recommend growing it in the ground outside unless you live in one of the UK microclimates and are unlikely to suffer frosts.
Yucca Plant Types
There are a great number of Yucca plants including hybrids although in the UK the list of readily available plants is short. The Yucca plants for sale are available to buy in Britain and are grown in our climate. They range in hardiness where all can be grown in milder parts of the country and many over all of the UK.
Yucca prefer well drained soil and do not tolerate damp ground in winter or under very cold conditions. Growing them in raised ground, where the soil drainage has been improved or growing them in pots is suggested especially if you live in a region prone to extreme cold or excessive rainfall in winter.
The tall Yuccas are the ones producing a stem as opposed to those that grow close to the ground and tend to be clumping. If you are looking for a trunked or large Yucca plant it is going to be more expensive on account of the number of years it takes for them to grow to a mature size.
Yucca gloriosa (Spanish Dagger)
The most commonly seen outdoor Yucca that is probably the most proven in our damp climate. Over time they will produce a trunk becoming a Yucca tree and in summer produce a tall spike of creamy white flowers which is quite spectacular.
The sword shaped foliage is quite stiff and sharp so it should be grown close to where people or pets walk by. You also have to be careful when handling them, you can quite easily cut your hand or get poked in the eye by the tips of the foliage if you are not careful.
They can grow up to over 2 metres but not much taller so will suit most gardens. They are also very tough taking temperatures down to -15°C.
Yucca gloriosa 'Variegata'
A variegated version where the leaf edges are a cream or yellowish colour that can turn pinkish red. Not as readily available as the standard green leaved Y. gloriosa. It is also just as hardy as the plain leaved variety.
Yucca gloriosa 'Bright Star'
A variegated Yucca with more distinct variegation than Y. gloriosa variegata with brighter and more of a yellow colour to the edges. There are also finer variegation over the green central part of the sword like leaves.
Yucca Bright Star is a beautiful looking Yucca that is also very hardy here in the UK. A great alternative to Phormium for those who live in colder parts of the UK and find that their colourful Phormiums are getting cold and wind damage in winter.
Yucca filamentosa (Adam's needle and thread)
Another hardy Yucca is Y. filamentosa taking temperatures down to -15°C, not all the varieties are this hardy so I am only going to mention the two Yucca filamentosa variants that are the hardiest and are available to buy in the UK.
As you can see from the picture above the standard green variety looks good even in January. The sword shaped strappy leaves are softer than Gloriosa and they are also low growing, clump forming and do not produce a trunk or stem.
They prefer a dry sunny spot and are not demanding plants. They are great for mediterranean or tropical style gardens without requiring the hot weather. You can also try them in pots as they are not going to require constant watering.
Yucca filamentosa 'Color Guard' (variegated needle palm)
If you want a more colourful variant then Color Guard has a bright yellow central stipe to its leaves. It is more or less identical to the green version just brighter. It is one of the hardiest variegated clumping Yuccas so ideal for the UK.
Yucca filamentosa 'Bright Edge'
If you want a variegated Yucca with the variegation around the edges then Yucca Bright Edge has green leaves with a thin yellow margin around the edges. According to the RHS3 this variant is not as hardy with minimum temperatures down to -10°C although Havliz has this listed down to -29°C4.
Blueish green sword shaped leaves and very similar in appearance to Yucca gloriosa except the foliage is softer, more curved hence one of the common names being Soft Leaved Yucca.
Y. recurvifolia is not commonly available in the UK but I think is such a good looking plant that its worth buying if you see it available. Hardiness is in the region of -15°C probably being its lowest temperature as specific numbers are hard to pin down.
Yucca recurvifolia 'Monca' aka 'Banana Split'
A sport of Yucca recurvifolia and a bright and tropical looking one at that is Yucca recurvifolia 'Monca' also more commonly known as Yucca recurvifolia 'Banana Split' which pretty much sums up its appearance.
Again as with the green form of this soft leaved or curved leaf Yucca it is well worth seeking it out. Hardy, bright and tropical but able to easily withstand our UK climate with A l'ombre des figuiers5 citing it can take temperatures down to -20°C.
Yucca aloifolia purpurea
I have only recently been growing Yucca aloifolia purpurea after seeing its stand out colour and stand out tropical appearance. The plain green Yucca aloifolia has an RHS H3 rating which means temperatures no lower than -5°C and this authority Yucca site recommends keeping them frost free.
The Yucca aloifolia purpurea hybrid seems to be much hardier than the standard green Yucca aloifolia.
Purpurea, which is purportedly a Yucca desmettiana hybrid has not been widley tested in UK conditions but My Palm Shop6 on the other hand lists Purpurea down to -13c. There are also reports of it taking -9c to -10c in the states and surviving.
The ones growing in my garden have been exposed to sub zero temperatures and have not experienced any leaf damage. I would recommend planting Purpurea in a well drained sunny spot with some shelter from wind and excess rain such as close to a south facing wall or fence.
As with most Yucca damp is the real enemy and a sunny spot will bring out the best in them. Purpurea benefits from direct sun as it enhances the purple colouring of the foliage. It will grow a trunk over time and look spectacular.
The leaves can be greener nearer the stem and the lower leaves if they do not get enough light. The mixture of green and purple does make this Yucca appear more visible in the garden.
Yucca plants for sale
Yucca is becoming more popular and the range of Yucca plants for sale is much broader than it used to be. The wider range of colours and the greater hardiness compared to the likes of Phormiums means that they are a great alternative or addition to other sword shape and strappy leaved plants.
Whilst the number of outdoor Yucca plants for sale in the mainstream garden centres is minimal if sometimes non-existent the smaller specialist nurseries have as usual filled the gap.
Supporting independent growers and sellers will ensure that the rarer and more unusual forms and cultivars are available to buy in the UK.
Yucca plant care
As long as they are given the right conditions these group of plants are a relatively low maintenance plants. They do not require regular watering, even in pots. They do require well drained soil and plenty of sun.
The only maintenance that is really required is to remove the sometimes very large flower spike after they have finished flowering. It also makes the Yucca appear tidier if you remove the older lower leaves which can be done infrequently.