Staking Plants - Or Maybe Not.

There’s nothing quite like a strong summer wind to highlight the topic of staking plants.  After weeks of mild breezes and strong growth it doesn’t take much to flatten summer annuals, perennials and even some shrubs. Vegetable plants aren’t immune either. Peas, beans and event broccoli might need a bit of support.

There are ways we can grow tall summer plants without staking and I’ll come to that later. Before that let’s assume you don’t have the perfect conditions to grow tall vegetables, annuals and perennials without them falling over. Generally it’s easier to get plant supports in place when they are young and don’t really need them. This will save disturbing the plants and roots later. For example I put a bamboo cage around my broad beans as I planted the seeds as I knew the plants would need it later. There are other reasons apart from height why plants need support. Brittle stems, falling under their own weight, drooping plants can damage lawns as they cut out the light and sometimes plants get leggy from overfeeding or not enough light.

Emergency staking is usually needed though as I found out this week when my annual lavatera ( also known as three month mallow) collapsed after a few summer gusts of wind.  I was going to leave them lying over the annual pots and grass but they looked too messy so I tied them to the fence with some string. They seem happy and I can get on with cutting the grass.

Some points to consider when staking

When choosing the most suitable support, you need to match it to the vigour of the plant.

Don't tie in plants too rigidly; they should be able to move in the wind. Use soft jute in a figure of eight to avoid rubbing.

Single ring supports can be used to support stems of plans with large single blooms such oriental poppies and foxgloves.

Bushy clump-forming perennials such as aster bellflower and phlox grow well through netting or grow-through circular grid support frames.

Top-heavy plants such as herbaceous peony and dahlias are also well-suited to grow through circular grid supports or use Y-stake supports.

Pea-sticks are useful for both short front-of-the-border plants like penstemon, yarrow and flax.

Using border restrains is practical way to keep the front of the border neat and prevent flopping plants damaging the lawn.

No Staking – Maybe

There are other tactics to keep plants looking good and standing tall. Things like soil, spacing, light, water, and pruning practices not only influence a plant’s leaf and flower production but also have an impact on its overall stature. By being mindful of how these elements play a role in the plants growth and size you could have a nearly stake-free garden.  

Choose the right spot and soil for the plants. Clumping plants together like you would with broad beans and sweetcorn can be useful, but the outside of the clump will still need staking. Other plants won’t like being in such close proximity to one another and can get leggy or a fungal disease because of lack of air flow. Get to know your plants’ mature size at planting time and space them accordingly.

Check out the plants location to see if the light and shade are to their liking. You will see seedlings get very leggy on a shaded windowsill and the habit will continue to maturity if not corrected.

Don’t forget to consider one of the most overlooked conditions in the garden: wind. This invisible force can wreak havoc on perennials, leaving them as flat as a pancake. Avoid placing garden beds in the path of a wind alley.

Regular watering is important too and that goes for container grown plants. The wind will dry the plants out really quickly even if there is no sun which could lead to stress and weakening of the stems.

One of the key things for me though to keep tall plants from falling over is to give them a seasonal pruning.  Late bloomers and historically floppy plants like asters benefit from a clipping.  Snip plants back by a third to a half in early summer for a shorter and bushier habit that will have little impact on the bloom. It’s also not a bad idea to stay on top of deadheading. This practice not only encourages more blooms but also promotes bushy growth; removes heavy, spent flowers; and redirects the plant’s energy back to healthy growth rather than to seed production.

I won’t stop staking plants though as creating flamboyant bamboo structures in the garden is one of my highlights of the spring and the first real opportunity I have to reintroduce myself to the dormant garden after winter.

Broccoli Roses and Shallots

 Flowering broccoli late or early?

I’m a bit confused about broccoli. I know there are varying types that produce flower heads in summer, autumn and spring. It’s just that this year I’ve got things completely wrong. 

I bought a purple sprouting type that I thought would give us a nice crop in early spring. It turns out these are a summer cropper. The ones I wanted were an “Early” variety. It turns out that early ones are the type that produce early next year, not early from the time they are sown. 

I’ve confused myself again (and probably you) but it gets even more confusing when you take bolting into consideration regardless of the flowering type. You can have early varieties that produce at this time of year because the soil is too hot and the plant gets stressed. 

The sunshine isn’t the issue it’s the hot soil that makes the plant think there’s no point in growing anymore and needs to throw out some seeds. I think if I mulched the base of the plants to keep the soil cool and kept them better watered in the dry spell I wouldn’t be adding the florets to every meal now trying to use them up. 

An excellent way to prevent broccoli flowers is to harvest early and frequently. Broccoli is a cut and come again vegetable, when you cut the main head, other smaller heads will grow. The side heads will take a little longer to bolt so I’ll be munching on them for a while yet if I’m lucky. 

Shallots

Talking of being confused. I have grown shallots for the first time this year and was a bit unsure when to harvest them. It turns out they are more or less treated the same way as onions. Shallots and onions are of the same family and share many characteristics. Shallot bulbs are smaller and, once grown, tend to have a milder flavour than onions. The main difference in the garden is that shallots form clumps of bulbs, whereas onions grow as individual bulbs. Regardless of this, they’re planted and grown in exactly the same way.  Onion and shallot sets are sold, like broccoli as spring or autumn planting varieties. 

I picked the green leaves to put in stir fries and curries earlier in the season until the leaves started to turn a bit yellow. I then pulled up the shallots and put them on a sunny shelf in the shed to dry off.

They came up really easily on a dry day and it was as though they were pushing themselves out of the ground. They should last for several months.

Black spot on Roses

I’ve had a few people tell me their roses have black spot this year. Black spot, curse of the rose garden, has been flourishing countrywide ever since sulphur pollution from smoky chimneys was reduced. The disease annually strips roses of their leaves. Spores from fallen leaves infect the soil and even if every infected leaf is picked off and burned, which is impossible, the cycle continues because more spores blow in on the wind.

Who would have thought that clean air would cause a problem in the garden?  One treatment seems to be to give the roses back their sulphur, which thankfully doesn’t mean introducing heavy industry into Inishowen as there are other ways to get sulphur to the plants.  Sulphur is not soluble, so you cannot spray it, and if you dump the stuff on the ground, it won’t break down. There is a soluble sulphur dioxide you can get and if you overlook the fact it is a by-product of the oil industry you can put the wettable mixture on your plant or add granules to the soil. This is said to actually prevent the black spot from forming compared to the commercial rose sprays, which aim to cure the problem only after it has arrived. You can live with the issue though, or like me, choose not to grow roses but appreciate them on other people’s gardens or parks.

Prevention

There are a few things you can do to minimise the issue without sulphur.

Mulching and keeping the plants healthy is the top of the list I think. Strong healthy plants will generally resist attack better those that are weak.  Regular raking around the plant with a hoe and good mulch will cover infected leaves if you can’t be bothered to lift and burn them.

Choose resistant varieties, but don't rely too heavily on resistance because there are many species of fungus and even new varieties can quickly succumb.

Slug Pellet Ban-Male Courgette Flowers-Springtails.

 Tiny springtails under the microscope

The days of using general slug pellets are nearly over. An announcement from DEFRA has banned metaldehyde slug pellets from Spring 2020.  They say "metaldehyde poses an unacceptable risk to birds and mammals."  The pellets being taken off the shelves contain metaldehyde or methiocarb. Don’t worry though, you won’t be needing to get the flashlight out to go into the garden at midnight on a slug hunt. There will be alternatives that claim to be less toxic to the environment. Some shops are stocking the new products now.

The new pellets are ferric phosphate based and are classified as suitable for use by the organic grower. They contain ferric phosphate or iron III phosphate, which affects the calcium metabolism in the gut system of snails and slugs causing them to stop feeding and die within three to six days.

Although the ferric phosphate is less toxic than metaldehyde, there remains the problem of the other ingredients in the tablets - known as chelators. These chemicals help bond the iron molecules and make them more toxic to the molluscs. Unfortunately they also affect earthworms, and, if consumed in large quantities, can poison pets.

There are other products coming to market such as the wool pellets but I have yet to see or hear anything positive about them. The compressed wool deters the slugs only until it gets wet, then the slugs crawl all over them so they are probably more effective in drier climates. They do work better than eggshells or coffee grounds though but at the moment are very expensive. Back to pellets then.

Courgettes

Our corgettes are finally doing something. For weeks now they have just sat there looking sorry for themselves but now have sprung into life with wild, reckless abandon. I think they have been using all of their energy to form roots ready for the growth spurt.  We did have a couple of male flowers initially which don’t produce the courgette and these probably come about to help pollinate the female flowers and entice insects such as bees who will return to the plants once the female flowers are produced.

You can make use of some of these male flowers by deep-frying them, though make sure you leave enough on the plant to ensure successful pollination. You'll know when your plants have started to produce female flowers, because female flowers have an immature courgette fruit behind them, while the male flowers are produced on long, thin stalks with no such swelling.

Courgette Tip

The trick to avoiding a glut of courgettes is to pick them while they are still small - anything up to about 20cm (8in) - and to pick them regularly. Picking and eating some of the male flowers will also help to slow production.

Springtails

The damp conditions have been a perfect breeding ground for springtails. You might have never seen one of these six legged creatures because they are only a couple of millimetres in size.

Springtails (Collembola) can be prolific with 100,000 reputed to live in each cubic metre of top soil. Most have a tail-like appendage folded up under their abdomen called a furcula which is held under tension. If they feel threatened it can be released to catapult them into the air to escape. They don’t seem to care where they spring to when disturbed and can spring anywhere.

They live in soil and in leaf litter where they eat mainly decaying plant material, fungi and bacteria. Some species are believed to feed on algae, pollen and insect faeces.

I have found the small creatures (that are not classified as insects but ‘Entognatha’) mainly in small plug cells where moisture and algae can sit making them perfect environments for them. When I repot or pack plant plugs I give them a few sharp taps on a hard surface and the springtails fall out and scuttle away.

When numbers reach outbreak levels springtails may be found indoors on floors and around windows. Ponds are occasionally covered with a fine scum made up of millions of tiny springtails floating on the water surface.

Control

Springtails aren’t usually an issue but they can take over your houseplant soil if it is wet and they do make you feel like scratching when you see them. They usually die off quickly when the soil dries out without the need for any chemicals.

Gunnera

Have you have ever come across a mature gunnera plant? 

If you have I’m sure it’s something you’ll never forget. From a distance they just look like a clump of rhubarb leaves, but get closer and this herbaceous perennial just seem to grow and grow. Reports of 3 metre high leaves with a 2m leaf span are regularly documented. 

It is one of those architectural plants, like the giant hogweed, whose scale astounded Europeans and made it the must-have ornamental/ edible plant for 19th century horticultural fashionistas and collectors. In Ireland, Kylemore Abbey (Co Galway) and Ilnacullin (Co Cork) planted them up. They were more recently introduced into the Irish gardens but then this triffid-like plant has escaped and naturalised along swathes of Irish coastline as well as along riverbeds, coastal cliffs and forest margins.

The biggest problems are now in particular on Achill Island and in Counties Mayo and Galway where they are classed as an invasive weed

There are two main types of large gunnera. There’s the manicata variety that isn’t invasive and sold in garden centres then there’s the tinctoria which gives us the problems. There are loads of others too down to tiny 10cm high groundcover called monoica but are overshadowed (groan) by their larger cousins.

Gunnera tinctoria produces a large cone-shaped flower head from spring to early summer, with small flowers. The fruit is orange. It is a deciduous plant whose leaves die back in autumn (October) commonly leaving the large brown rhizomes exposed. The flower clusters on the stems occurs early in the spring, with the fruits maturing in late summer/early autumn. Large numbers (up to 250 000 seeds per mature plant) of drupe like, red or orange seeds are produced. Small fragments of the rhizome have the potential to establish new plants.

Growth starts in early spring (March) It can reproduce by both sexual (seed) and asexual (vegetative) means.

Problems caused by Gunnera tinctoria

Due to Gunnera’s wide leaf span, large dense cover can have a dramatic impact on the local biodiversity by light exclusion. On rivers it causes erosion to banks, exposing them to fast running water after die-back in winter. When the plant dies back its dead leaves fall into watercourses and can block drains and watercourses, resulting in flooding. It can also alter the visual aspect of once beautiful landscape vistas, by rapidly colonising large tracts of fallow ground.

While Gunnera has become a major problem in the west of Ireland, INVAS Biosecurity believes in its mission statement of providing the “first line of defence”, and that preventative eradication programs should be put in place now by those stakeholders whose responsibility it is to protect our environment. This would be extremely cost effective both in the short-term, and save millions in the long-term. 

INVAS

Invas Biosecurity, a private company in Dublin are among a growing number of companies that want to control invasive species in the countryside. They can carry out baseline distribution surveys, risk assessments and develop comprehensive management plans, which include spraying, Rhizome injection, Cut and paint herbicide injections in much the same way Japanese Knotweed is controlled. Biodiversity Ireland would also like you to report any sightings of the plant if you see them in the countryside (not in your neighbours garden I don’t think).

Care for gunnera in your garden

Larger gardens can showcase the gunnera manicata and keep it under control without issues. One thing that stops the plant in its tracks are temperatures lower than -8°C, so a good hard frost will kill them off unless they are well wrapped up with dead leaves. If you have a smaller variety in the garden you will probably cover the crowns with dry mulch. The leaves of larger varieties could be cut off after the first hard frost. Inverted, the leaves provide excellent coverage for the resting crowns.

Another method to help keep out moisture is to remove leaves after the frost, cover the crown with  60cm of straw, cover with a burlap tarp, or large plastic container, such as a tub, and then add another 60cm of straw. Seasoned wood chips or sawdust will work even better. After all danger of a hard freeze is gone, in late March or early April, protection can be removed. 

Just to say again, it’s reckoned that G. manicata – the Chilean one – doesn't share its Brazilian cousin's invasive nature. So perhaps this should be your preferred Gunnera should you have the time and space to grow one.