If your sweet peas are a bit more flop than fabulous then this is the guide for you. Here I have collected together the most common sweet pea problems and assembled them into one simple guide.
I’m sure you will find your sweet pea problem here, and more importantly, a fix!
Why are my sweet peas turning yellow? (Or Brown!)
There aren’t many better flower displays than a wall of sweet peas in full, glorious bloom.
But what if your sweet peas are a little more yellow than glorious? What causes this and what can you do about sweet peas turning yellow, let’s have a look!
If sweet peas are sat in very damp soil all of the time then they can suffer from a problem called root rot.
This is just as the name would suggest, the roots begin to rot from all the moisture. This will cause the ends of the leaves to turn yellow and start to curl.
Sweet peas do like fairly moist soil so to have this issue they have to be really overwatered. This can happen in pots that don’t have proper draining and leave the roots of the plant sitting in water.
Root rot causes the same issues as damaging the roots by transplanting; the solution is the same.
The plant needs time to recover and less water.
This is obviously easier to control if they are in a pot, if your sweet peas are in the ground then it may be a job for the following season to improve the drainage in that area.
Transplanting / Root Damage
All pea plants, including sweet peas, do not like to be moved or have their roots disturbed.
If you have just moved your sweet peas or potted them onto a bigger pot then this could well be the reason the leaves are turning yellow.
If this is the case then simply leaving the plants to recover will be enough to see the yellowing reversed.
If you have severely damaged the roots while transplanting then it may take a couple of weeks for them to find their feet again.
Infections / Viruses
Brown and or yellow leaves in any plant can be a sign of illness in the plant caused by an infection or virus.
Look for an irregular, mosiac-like, colouring on the leaves as a sure sign of a viral infection.
With short-lived annuals like sweet peas, there is really not much you can do about this, and it really isn’t worth the effort to try and save the plant.
If it is looking fairly bad then you may want to remove the sweet peas from the garden to remove the risk of the illness spreading.
Whatever you do, don’t put the dead sweet peas on your compost heap as you may risk spreading whatever was affecting them all over your garden.
What is eating my sweet peas?
Sweet peas are glorious flowers, but also attract many pests and are a favourite snack for many.
If you notice some bite marks on your sweet pea leaves you will obviously want to know what is eating on them. So let’s have a look at some of the more common pests that could be eating your sweet peas.
Slugs and Snails
The most common pests that will eat your sweet peas are slugs and snails. They love sweet peas, particularly when they are young.
Look for slime trails and unevenly eaten edges of leaves. These are textbook signs that your sweet pea plants are being eaten by slugs and or snails.
If not dealt with they can completely eat and kill younger sweet pea plants, older ones should be able to shrug them off without much issue.
to deal with slugs and snails you could buy pellets if you aren’t worried about gardening organically. If you do want to be organic then you still have a few options.
You could set beer traps, use distraction plants or use some nematodes if you want an easier way of killing off slugs.
Leaf miner is the common name given to the larvae of several Beatles and flys. These larvae create winding random trails over the leaves of plants as they eat them.
These larvae are actually inside the leaf so you won’t spot anything other than the damage on the surface.
Leaf miners aren’t much of an issue for larger plants and usually only affect a few plants which you can remove by hand.
They can be more of a pain on younger plants, and I believe there are commercial sprays available to deal with them.
The easiest way to check for caterpillars is to look at the underside of the leaf. If caterpillars are your problem you will usually spot them fairly quickly.
There will also be uneven bite marks from the edge of the leaves.
Usually a springtime pest, pea weevil can wreak havoc on young sweet peas. Look for very irregular lumps taken out of only the edges of the leaves.
Pea weevils are usually only active in spring and usually only affect the lower leaves on your plants so don’t tend to be too much of an issue.
Birds are known to sit on sweet pea trellis and eat the flowers clean off. There won’t be much sign of destruction apart from missing flowers!
The only real way to know if it is birds eating your sweet peas is to lie in wait and try and catch them in the act.
My Sweet Peas Are Not Flowering
If you are excitedly waiting for your sweet peas to bloom but it just doesn’t seem to be happening then what can you do?
Here I have some of the main reasons why sweet peas won’t flower and what you can do about each of them.
Not enough sun
Sweet peas love being in full sun, if they are deprived of enough sunlight then this can result in them not flowering.
Of all the reasons that your sweet peas might not be flowering then I would say this is the most likely.
The easiest way to tell is to observe your sweet peas and see how much sunlight they get. Ideally, you want them to be in direct sunlight for at least 6 hours a day.
Not enough water
Sweet peas are thirsty plants and if you are growing them in containers or we have had a dry spell then they will need plenty of additional watering.
If they don’t get enough water then sometimes they can refuse to flower, or flower a lot less than usual.
This one isn’t really much of an issue for UK gardeners unless we get an extended heat wave. Like all peas, sweet peas are suited to really hot conditions.
Heat stress from extreme heat can stop them from producing flowers.
How do I get my sweet peas to flower?
If you think the issue is that they are not getting enough sun then you can try to move them, but be warned, they don’t like being moved.
Maybe wait until next year and grow them in a different position.
Watering the plants regularly can help if they have got dried out by an extended dry spell.
With too much heat there is not much you can really do for the plants apart from making sure they have plenty of water and waiting for the weather to turn, which let’s be honest, it will do.
When do sweet peas flower?
Sweet peas are usually expected to start flowering in June and can flower for the remained of the summer. If you regularly prune the flowers you can even get them to flower well into autumn.
Why are my sweet peas wilting?
Everyone loves the sight of sweet peas in full bloom, and there is the simply delightful scent they also provide. But what do you do if those wonderful sweet peas that you have put so much effort into growing start to wilt?
Why could your sweet peas be wilting?
Transplanting / Root Damage
All pea plants including sweet peas do not like to be moved or have their roots disturbed. If you have just moved your sweet peas or potted them onto a bigger pot then this could well be the reason they are wilting.
If this is the case then simply leaving the plants to recover will be enough to see the wilting reversed.
Sweet peas are not the most sensitive plant to overwatering but if you really do overdo it then you can end up with some issues-particularly in young plants.
If you keep your seedlings in permanently damp soil then you run the risk of introducing root rot.
Why are my sweet peas leggy?
If you are starting your sweet peas indoors then you may run into an issue where the young seedlings become really leggy and long and spindly. T
his is a common issue with many seedlings started indoors and happens particularly with those that are more suited to colder conditions, such as sweet peas.
there are two main reasons why your sweet pea seedlings will be leggy, light and heat.
Not enough light
This is the most common reason for pretty much all seedlings going leggy. They simply aren’t getting enough sunlight so they stretch and strain to reach for the light.
This is very common with seedlings starting early on windowsills in the UK.
Without being in the light all day there simply isn’t enough sun during winter/early spring on most windowsills unless they happen to be in direct sunlight all day long.
Too much heat
Sweet peas are cold-loving hardy plants, they don’t need to be in warm conditions to grow properly.
In fact, warm conditions can sometimes cause sweet peas to grow really leggy as the conditions are too good for them.
If you think your seedlings are getting enough light but are still growing leggy then this may be the reason why and you should think about moving them outside.
How to save leggy sweet peas
If your sweet pea seedlings have gone a little leggy then don’t worry, there is still plenty you can do to save them.
To start with sweet peas should be pinched out anyway. This encourages bushier growth which in turn leads to more flowers.
You can cut the main stem of sweet peas back to just two pairs of leaves. This seems really harsh but believe me, it is good for the plant in the long term.
You should also think about moving your sweet peas outside, the cold won’t do them any harm at all and will stop them from growing leggy again as long as they have enough light.
You will want to do this gradually over a couple of weeks.
Don’t do both these things at the exact same time as the double shock could be too much for them. Pinch the tip out then give them at least a week to recover before you start moving the seedling outside.