Persian Everlasting Pea

The Persian Everlasting Pea.

Lathyrus rotundifolius or persian everlasting pea on the fence at Easton Walled Gardens

Lathyrus rotundifolius

‘You’ll never sell it’ said nurseryman Tim as he delivered plants for our visitors back in the day. Sure enough, by September, when all the gifted 1 litre container plants had gone to kind homes; two scraggy looking pots were left. Lathyrus rotundifolius, also called the Persian everlasting pea, doesn’t take kindly to being restricted so we released them into the border along the pickery fence and rather forgot about them.

Next summer something remarkable happened. Beautiful twining stems rose from the ground and romped over the fence (politely leaving space for other climbers.) By July, the plant was smothered in pink flowers that contrasted beautifully with the foliage. It has been one of the most asked about plants in the garden ever since.

Lathyrus rotundifolius or persian everlasting pea at Easton Walled Gardens

Habit and provenance:

Hailing from the countries around the Black Sea and into Iran, the Persian everlasting pea grows in meadows with other leguminous plants. A member of the prettily named sub-family Papilionaceae (meaning ‘butterfly–like’), it uses tendrils to climb and support itself and growth is prolific between April and June.

The flowering stems form racemes of 3+ flowers, cream in bud and darkening as the flowers open. The flower colour is often described as brick-red, although in our experience that is the colour the camera lens sees. On our plants, the petals are a deep pink with increasing blue tones as the flower ages. There is no discernable scent but that doesn’t stop insects including bees foraging in the flower heads.

Lathyrus rotundifolius or persian everlasting pea flowering stages copyright Easton Walled Gardens

How to grow:

Lathyrus rotundifolius plants are hardy (H7 on the new RHS ratings system), herbaceous perennials. They grow best in reasonable soil in full sun or dappled shade. They need something sturdy to climb and our Im fence is the perfect vehicle. If trained the plant may make 1.5m.

Despite its aversion to small pots, Lathryus rotundifolius makes a well behaved addition to large permanently planted containers. We have some outside the shop door and they climb and flop over the edge with great charm.

persian everlasting pea in container at Easton Walled Gardens

As the top growth dies back in autumn the stems can be cut back to ground level and used on the compost heap. In the spring, bulbs such as tulips, crocuses and snowdrops fit snugly around the roots and will give you lots of colour until the pea starts to grow again.

Mary Keen describes the roots as ‘wandering’, which is about right. Propagate from Irishman’s cuttings (a piece of stem with roots on) in late spring. The seed tends not to set in northern areas and germination can be slow.

We offer pots of this pea for sale in June and early July, if you would like to reserve one please contact the office.

Top five nurseries at RHS Chelsea

Top 5 growers and their plants at RHS Chelsea

Eagles Sweet Peas

..have had a tough growing year to get enough sweet peas together but you would never know. Owner Derek Heathcote brought his usual quality display to Chelsea and added another gold medal to his collection.

New to his stand this year was Sweet Pea ‘Ballerina Blue’ described as ‘a must for exhibition and cut flowers.’ It has four large pale blue florets per stem, a good scent and has been awarded an AGM. It was good to see one of my favourite sweet peas Henry Thomas on his stand.

Swapping sweet pea stories with such an experienced grower was always going to be interesting and we nodded wisely together over his mantra: ‘It’s a good root system that produces the flowers.’

Derek Heathcote of Eagle Sweet Peas at RHS Chelsea Flower Show Richard and Heather Godard-Key from Fibrex Nurseries at RHS Chelsea Flower Show

Fibrex Nurseries

Owned by Richard and Heather Godard-Key (see above in front of their gold medal winning stand), Fibrex Nurseries is the go-to place for heritage, modern, specie and scented pelargoniums (still known colloquially as geraniums). With over 2,500 varieties in their collection, pinning down a favourite was always going to be hard but we did discuss their top three scented geraniums: ‘Attar of Roses,’ ‘Lemon Fancy’ and ‘Lady Plymouth’. Surprisingly, I learnt that regal pelargoniums are particularly good for bees.

Hardy’s Cottage Garden Plants

Rosy Hardy is one of our plant heroes and if she recommends a herbaceous perennial it’s worth listening! In 2013, Hardy’s championed Nepeta grandiflora ‘Summer Magic’ and it was featured on their stand this year. It has gone straight onto my bucket list along with this year’s introduction Antirrhinum ‘Pretty in Pink’ – This is a perennial, rust resistant snapdragon with a long flowering period. Sounds perfect to us and well worth trialling next year.

Rosie Hardy at RHS Chelsea Flower Show 2015 Antirrhinum 'Pretty in Pink'

Trewidden Nurseries

The most south westerly nursery in the country specialising in exotic plants. The Aeonium display stopped me in my tracks. Most of us are familiar with A. ‘Schwarzkopf’ – often resembling a walking stick with black succulent leaves on rosettes sticking out of the top; this plant is really only suitable for big container schemes. Trewidden are offering homebred Aeoniums ‘Du Rozzen’ ‘Merry Maiden’ and ‘Poldark’ which are far more compact for low maintenance container plantings.

Intriguing Proteas and other exotics will make this nursery well worth visiting online when it rebrands as Penberth Plants in the autumn.

Robinsons Seeds and Vegetables

Susan Robinson is part of this legendary vegetable growing family. Many of their vegetables, forced over the winter in challenging conditions, are also good for a family garden. A small tender cabbage, Hisp F1, that can be used like lettuce early in the season, featured in the front of her display. Its size makes it a good choice for supper without leaving mountains of cabbage to lurk in the fridge.

Her comment to me that ‘Fruit and veg should hover between life and death’ (under stress the plant puts all its nutrients into the edible parts) was music to my ears. There is now an excellent excuse for deprived tomato plants.

Susan Robinson at RHS Chelsea Flower Show Tomato tower at RHS Chelsea Flower Show

 

You may also like: Top 5 things we learnt at RHS Chelsea.

How to grow autumn sown sweet peas

Autumn sown sweet peas from Easton Walled GardensWhy should I grow autumn sown sweet peas?

Hardy annuals, like sweet peas, will grow, flower and die in one year. By sowing in the Autumn instead of the Spring you give the plant 6 months of extra growth. By next summer they are able to sustain bigger, earlier flowers on strong stems.

You also have two seasons to sow (Autumn and Spring) to guarantee success and a longer flowering period. Flowering dates vary from year to year so a succession of sweet peas is particularly important if you plan to have your own beautiful flowers for a wedding or family celebration.

Is it more complicated than sowing in the Spring?

Yes and No.

Yes, you will have to care for your plants over winter.

No, you will have virtually indestructible plants by the time they go out into the  soil.

Ok, so you have sort of convinced me, how do I go about it?

You will need the following:

Deep pots such as roottrainers or long tom pots and some multi-purpose compost with a slow release fertiliser added (that’s included in almost all commercial composts).

A place to put your sweet peas where they will get plenty of cold but won’t be as exposed as if they were in the open garden. A porch, cold frame or unheated greenhouse is ideal.

Anything else?

Seeds obviously (which you can buy from us here). The other thing to consider is mice. They LOVE sweet peas when they are seeds or very small seedlings. Protect your pots so mice can’t get access to the seed. That could be anything from a platform with legs that are tucked underneath so the mice can’t make it past the overhang or a clear lid to cover your sweet peas (Roottrainers supply these with the pots)

Keep an eye out for slugs too by checking the base of your pots (where they love to lurk) and removing them.

When should I sow my seeds?

You can sow anytime from early October to mid November when the days allow for a long gentle germination. Push them gently into the damp but not wet compost until they are covered by about 2cms of soil.

How do I know if I am getting it right?

What you are aiming for is lots of roots and the minimum of top growth. If you see green shoots emerging slowly and gradually putting on leaves over a period of about 3 weeks you have got it right. If your plants are turning into a jungle of green you have got them too warm and they need to go somewhere cooler to slow their growth for a bit.

But how cold is too cold?

Sweet peas can withstand temperatures of about -5 at night but will not like to be frozen in their pots all day. If you overdo it and lose the top growth, chances are, if you give them some warmth they will have established enough root to sprout again.

I’ve completely overdone it and my plants look like triffids, what should I do?

Pinch out the main stem back to 2 sets of leaves with your finger and thumb to reduce the top growth and send your plants to the sin bin as detailed above. If you have had them on a windowsill or similar, be careful not to abandon them to the cold too fast. They will need hardening off. Put them outside in the day time and bring in at night for a week before leaving them out full time.

It’s Spring! My plants are busting to go out, when should I put them in the ground?

This depends a lot on where you live but once the worst frosts are over is a good time. For us in Lincolnshire this is from Mid-March onwards. A good test is to put your hand on the ground every few days and you will gradually start to feel the soil is no longer arctic. Keep an eye out for weed seedlings appearing, this is a good indicator that your plants will also put on growth in the ground.

I still have more questions, can you help?

As well as seed and roottrainers we sell Roger Parsons excellent book on Sweet Peas in our online shop. If you need help with individual problems you can send us a tweet @ewgardens.