Learning how to water plants to increase growth in pots, container or garden - especially how to water roots and tubers. Specialities: root growth or tuber growth of lawns, fuchsias, geraniums, dahlias and begonias.

26 June 2010

Blackfly Bonanza

blackfly colony on dahliasThis colony of blackfly was found on bedding dahlias in tub.

If left, they will suck the life out of the plants in no time. All aphids carry virus disease, as well.






'provado ultimate bug killer'Treated with 'Provado Ultimate Bug Killer'. This is very good stuff and can be used on all sorts of plants. One application protected the roses nearly all season, last year.

Caterpillar Party

caterpillar on euonymusTalk about devastation. Never seen a shrub stripped so quickly. Caterpillars have decimated this euonymus within about two days. Absolutely hundreds of them.

Caterpillars are always a problem in summer, but never seen them on this shrub before. Strange. Never even seen any moths or butterflies.

Dusted thoroughly with 'Derris Dust'. Don't yet know if it has worked. They were not exactly falling off the shrub when I left it. Will have to check again tomorrow.

These pests (different species but still caterpillars) are also a problem on dahlias and geraniums.

Keep your eyes open. This unusually dry weather could cause all sorts of unexpected problems.

P.S.

provado sprayNo response to 'Derris' after two hours. Used 'Provado Ultimate Bug Killer Spray' for first time. This is the first liquid pesticide I have seen which will kill caterpillars. It is also systemic and long-lasting.

P.P.S.

Think caterpillars are sawfly larvae. Was confused by black heads (thought they were orange). This certainly makes sense; they can devastate plants in days.

Tomato Problems

tomato plantsThings not good with tomatoes. The stunted plant was originally the better of the two.






meristem affected by weedkillerThis curled shoot tip is a sign of weedkiller damage. Roots have grown right down and out through holes at bottom of pot. Must have picked up some weedkiller from cracks in flags. Strange thing is, I don't remember using any weedkiller there. I never do. Another mystery.

I took a cutting from a sideshoot, which has now rooted. But I think it is too late to be of any use. Wouldn't fancy eating tomatoes off this plant, even if it recovers. Will keep it a while longer to see what happens.

Removed protruding roots and placed both pots on a plastic bin liner. Should have used one before. But they soon make everything look untidy.

Good news is that the better plant is really starting to grow now, after its bad start, weatherwise.

P.S. Tub insulation works a treat. Compost really cool, even in mid-day sun

24 June 2010

Water Crisis

Things have really moved on this week, with talk of hosepipe bans and the like. Decided to stop cutting lawn until further notice. The risk of cutting at this stage is too great. I just don't think it could stand it.

But there is hope. After all, we all know how quickly British weather can change - nearly as fast as me.

Seriously, it looks as if the writing is on the wall. Time to batten down the hatches and cut down on further water loss in garden by any possible means:
  • loosen soil surface
  • keep soil covered
  • keep cool, if possible (move to shade, or insulate pots)
  • avoid soil disturbance around plant roots

Clever Plants Can Play Flute

fluted begonia leavesAlthough all plants prefer the environmental conditions of their area of origin, almost all will adapt, even to those which might appear quite alien.

Look how these begonia leaves have grown narrow and fluted (they are usually broad and flat) to adapt to hot mid-day sun (begonias prefer dappled shade).

We need to take great care when moving a pot (e.g. when feeling the weight before watering), to place it back in the same position. As you can imagine, a slight rotation could be extremely detrimental, especially since it takes the plant some time to adapt. In mid summer, by the time it has re-adjusted, much damage could have occurred.

Generally aim to provide ideal conditions, if you can. You will get much better flowers, both in colour and in longevity, if you can do this.

Blackspotted Rose

rose blackspot on leafFirst blackspot of season found today. Disappointing: Already been sprayed with a systemic (moves around within plant) combined insecticide/fungicide ('RoseClear 3').

Bush is in a damp dark corner, so cannot expect too much. Sprayed all roses with 'Dithane', especially around base of plant and soil surface. Seems to produce better results.

As usual, this disease has first appeared on the lower leaves, probably because spores have splashed up from soil surface, where they over-winter.

Blackspot is not really serious - except cosmetically - Plants look bad. Removing lower leaves has no effect and is not noticed. It's when it gets half-way up stem that things become serious.

22 June 2010

First Dahlia Buds

first dahlia bud of yearThis bud is on the same dahlia you saw earlier. Don't know why it is flowering so soon, still a good 30 cm short of its full height. I said it had been a strange year!

Perils of Over-Feeding

I have deliberated long and hard over this article - ever since you (I haven't got any) planted the bedding plants - and even before this. Why? Well, it's just that feeding is so important - Although not so important as it is to us. I mean, plants don't actually die if left for a while without food, not directly at least (if they do die, it is usually because they have been weakened and attacked by predators or disease). In fact, food shortage is not the real problem - TOO MUCH food is the problem.

Plants don't get fat, have a heart attack and keel over like we humans, nothing like that. No, it's altogether more clinical. Being too liberal with the feed bottle (as we seem to have been conditioned to become) burns the tender young root hairs, thus depriving the plant of water (and, ironically, food).

I must be honest, I am lucky in this respect (the feeding, not the honesty). Being, as I am, too stingy to buy the feed, I don't really have this over-feeding problem. And, additionally, for some reason I am conditioned to appreciate the perils involved (feeding a plant gives me the same feeling as putting my hand near a hot stove: I want to draw it back immediately; it feels like some mysterious force is controlling the process (that reminds me, the appointment with the psychiatrist is due any day now)). Nevertheless, I do appreciate the significance. Next to over-watering, over-feeding is the second most common sin - er, error.

So, how DO we feed?

Well, after carefully honing my skills over the years, I have produced the almost perfect technique - one which has given me excellent results, and will for you, as well, I am sure. If you can bear it, I shall be pleased to share this technique with you, right here and right now (What was that? 'About ***** time?').

Upon receiving a new plant, and after having given it a brief but thorough perusal, I ask myself one question: Is it green? If 'Yes', leave it alone - do nothing for now; if 'No', again do nothing. Simple.

In case you think I am being facetious - I am not. No, really. You don't understand. This IS how you do it. It took me
years to discover the secret. Honestly.

Queen Delphinium

dawning delphiniumIs it any wonder the delphinium is called 'The Queen of the Border'? These plants look majestic at any time, in any form, and almost at any stage. Once flowering starts, we know summer has really arrived. This certainly seems to be the case this year. If only I could show you the full subtle range of tones.

delphinium petal

20 June 2010

Lawn Cuttings Returned

Did not know whether to cut lawn, or not, yesterday. Whilst never a good idea to cut in hot dry weather, especially when water reserves are getting low, the grass could grow so long that cutting it might give too much of a shock.

So I cut it at maximum height (3/4 inch on my mower, though would have preferred 1 inch) and removed grass box so cuttings returned to surface. This should provide some extra insulation against hot sun, thus conserving water.

I waited 'til evening before cutting, to minimise water loss through bleeding from cut leaves. Lawn looks good this morning; we shall have to see how long this lasts.

Roses Fed

Gave roses a feed of 5-5-10 granular (broadcast as granules on the surface) last week, about 20 mls per plant (2/3 oz (half a handful). It will need watering-in soon if it doesn't rain, although there is not much danger of scorching the roots as the plants are old enough to have deep roots. The feed is quite safe on the surface. The problem would arise if we got just a small amount of rain, producing a very strong solution of feed. If this happened, I would give water.

But having said this, it is important the plants do not become dry whilst flowers are forming. This is the time of maximum water requirement. So might give each plant about a 4.5 litres (1 gallon) of tap water, whether it rains or not.

The plants would then be set up with feed and water to supply the second flush of flowers (Yes, I know that we haven't yet had the first flush, but it is important to think ahead: quality growth is a slow process).

Dahlias Watered

Gave dahlias in beds some water yesterday. Didn't really have to. They have managed so far with only rain water. But recent dry wind could have been a bit too much. And with the dry weather forecast to continue, I thought it might be a good idea to give some help. So gave each plant about 2.25 litres (half a gallon) of plain tap water.

Seems to have done good; they have grown overnight. This often happens, since plants divide their cells and await water to fill and expand, producing an apparently wonderous growth. Plants are a lot cleverer than we think.

Hedge-Cutting Left

Although the hedge needs cutting, I have left it in this hot weather to keep up its strength. It has been so cold and dry this year that it hasn't grown very much. Another week or two will not hurt.

16 June 2010

Barking Saxifrage

bark mulchA bark mulch can look attractive in the right setting. It provides a good mulching tool and is effective at reducing soil temperatures and water-loss.

Now is a good time to apply a mulch, whilst the soil is moist after recent rain. Rhododendrons and azaleas benefit considerably from mulching.

Dis-budding Roses

rose budsRemoving the two secondary buds and leaving the larger top bud (centre) will divert all the food to this bud, thus making it larger. Now is a good time to do this dis-budding. It is a useful trick to try on lots of your flowers which form in groups, especially if you want to impress.

The recent rain has come at just the right time for flowering. As said elsewhere, heavy watering whilst the buds are forming seems to give massive flowers.

Have decided to leave the secondary buds on, so we can go for maximum flowers.

Rampaging Lettuce

rampaging lettuceThe lettuce have really come on over the past week. They have done brilliantly, considering weather conditions at planting out (temperatures down to near freezing with an bitter wind). We haven't lost a single one. I did have a photo of what they looked like the next day, but it seems to have got lost.

To give a bit more room and light, the outside leaves can be picked off and used. More will come from the centre.

The slug prevention tape seems to have worked, as well.

P.S. Have just found a recipe for lettuce soup. Looks like I'm going to need it.

10 June 2010

Ground Cover is Also Cool

If you have ever appreciated the cool shade of a large tree canopy on a hot summer's day, you need to understand that the soil feels the same way. A great way to keep it cool is to cover it up - preferably with plants. Cover it with anything opaque. But please cover it.

vinca flower Ground cover plants provide an excellent permanent solution. The periwinkle is rather attractive, don't you think? Or you could use ivy, or something similar. These plants will grow in any soil, in virtually any conditions.

Hot sun on bare ground causes exponential water loss, especially on darker compacted soils. Even though plants still use water, their cover reduces this loss by a colossal amount. Keeping the roots cooler also helps the plant perform better.

And there is another benefit, which will most certainly appeal: Many weed seeds (and other seeds, as well) do not germinate in shade. So covering ground reduces weeding. How about that for a benefit?

Of course, there is also a downside - slugs and snails like ground cover, too. Oh dear. Decisions, decisions.

Super Cool Tomatoes

tomato pots insulated with aluminium foilYes, I know: It looks awful. But I like it. No I don't - But does it really matter if it works?

Of course, I cannot yet answer that in the affirmative - it is far too early - and the summer has suddenly disappeared. But we should soon find out. I was so convinced it would actually work that I did both pots, instead of leaving one as a control.

In case you haven't yet guessed its purpose, can I just say that it is not so I can admire myself as I do the watering. No. The idea is to keep the compost temperatures super cool in hot weather. Do you remember that?

Roots need far more oxygen as the temperatures rise. And because more carbon dioxide is given off by respiration in the soil, the situation can become serious and impede growth.

But water loss also increases dramatically with temperature. Keeping things cooler conserves it.

The scrumpled newspapers on the top should allow air and water passage, whilst providing insulation. And aluminium foil is a great reflector, thus evening out the diurnal (day and night) temperatures. Brilliant. I really surpass and amaze myself at times.

But, seriously, it is quite common to find hot sun literally boiling the roots of plants kept in black plastic pots. Dark colours absorb far more heat. And if white pots (these are not too good because they allow light to get to the roots) lower the compost temperatures by about 4 deg C compared with normal colours, I cannot see how this could fail.

Clay pots are good for keeping plants cooler, but need more watering.

Dahlias Get Drink

Apart from rainfall, the dahlias planted out in spring have been given no water. But because they were planted deeply and because the soil surface has been kept loose for the first 3 to 5 cm, they are still growing. They say that dahlias need lots of feed and water. Well, this may be so. But mine are managing to do with little of each (apart from the bonemeal at planting, they haven't been fed, either).

So how do we know when to water, and how much to give?

I look for the first signs of temporary wilting. Most people rush to get the hosepipe at this stage. I don't - not necessarily. Temporary wilting occurs, usually in hot sun, when the roots cannot supply as much water as the leaves are losing. Once things are cooler, the plants will recover (if they don't recover by next morning, I water immediately).

So temporary wilting is not necessarily caused by shortage of water in the soil (although it could be); it might be because the sun is just too strong, or the leaves are drying too fast.

THE TIME TO WATER

Nevertheless, it is a warning. Once temporary wilting occurs more frequently (i.e. when this is not just a 'once-off'), it is time to water, especially if the plants have lost their bloom (this might be a better sign than wilting).

flagging dahliaThis is the same dahlia you saw recently. As you can see, the rain has arrived just in time: it is just starting to lose its bloom. It hasn't grown brilliantly. But it has done very well without additional water.


HOW MUCH WATER?

I would give each plant about 4.5 litres (1 gallon), as close to the stem as possible. This should be sufficient to get down to the roots, plus a bit more to to last about a week. This will help cut down on surface water loss (because this water will be held deeper in the soil), save time on watering, and reduce disease and pest problems.

Since every soil is different, it is a good idea to dig down, away from the roots, to see how wet the soil actually is at root depth. Then dig again after a couple of days, once things have settled down, to see how deep the water has gone.

As a rough guide, each square metre of ground will use between 12.5 mm (half-an-inch) and 25 mm (one inch) of water per week during the summer months. One inch (25 mm) is equivalent to applying about 4.5 gallons per square yard.

So we need to apply one gallon per plant at least once, if not twice per week. To conserve water, there is little point watering much beyond the width of the leaf canopy of each plant, which is the extent of the rooting system. This way there is limited wetting of the surface, thus conserving water. And the plants have had a really good drink.

Quality of Rain

Contrary to expectations, the recent rainfall has been on the gentle side (I was expecting a thunder storm). This is very good for soil structure: If the water can be absorbed as it falls, there is much less physical damage.

Problems arise when ponding occurs. That is, pools of unabsorbed water form on the surface. This whole layer gets stirred up into a sludge which then sets (and bakes, if done at mid-day) to a hard impervious pan (or cap).

This is a trap into which novice growers often fall with their bedding plants, especially in hot sunny weather. For some reason, they feel they are being kind to their plants by drowning them in water. No! This action is a real killer as far as the plants are concerned. Even if they survive, they will not prosper and will remain stunted; unless the surface pan is broken up so that the soil can breathe, once more.

Because we are always in a hurry, there is ever the temptation to apply water too forcefully, especially with hosepipes and sprinklers. We need to learn once more that patience is a virtue, when growing.

P.S.
It would be a good idea to go out and check your plants for panning. I cannot emphasise how valuable this advice is.

Feeding Tomatoes

Gave tomatoes 5mls of 'Phostrogen Plant Food' between them, in 4.5 litres (1 gallon) of water. A few of the flowers have now set, though it is still rather early. But I wanted to give them some water and feed to get some leaf growth.

When I look at everyone else's tomatoes, I feel quite ashamed; even though I know that too much leaf growth is not a good thing. But mine do look positively scrawny in comparison.

Apart from this, the tomatoes have not been watered since planting out, apart from rainfall. So much for developing a deep root system. It is proving difficult to dry them out.

If I let them dry out with the fruits on them, it will cause splitting. But it might be worth sacrificing (they can still be used) some fruits to get deep roots, even at this stage.

5 June 2010

Lonesome Greenfly

lonesome greenfly on rosesI was surprised to spot this greenfly on the roses this morning, because they have been sprayed. Perhaps it will just take one suck of sap and keel over, I don't know. But I sprayed the shoot tips again, just in case.

It is impossible to avoid aphid (greenfly and black fly) troubles on roses in hot weather, especially if they have been fed and have tender and juicy new shoots.

I know pesticides can poison other predator wildlife in the garden, but I believe that spraying has a deterrent effect and thus prevents attack by many pests. Hence, wildlife is relatively safe, albeit that they are not getting fed. This deterrent effect definitely works with slugs and snails, which will detect and avoid metaldeyde. I hoped it works with greenfly, as well. Perhaps it does. I am not sure.

By spraying before the flower buds open, there is less chance of affecting the bees. And it is definitely better than waiting until the plants are covered with (and hence devastated by) these aphids.

Toti What?

If ever you have fancied yourself as a cloning engineer, totipotency allows you to clone the plant's equivalent of 'Dolly-the-Sheep' and produce new plants either from a single cell or group of cells.

Cells contained in the meristems of plants (those areas of cell division and active growth) have this ability. Because the meristems are at the shoot and root tips, and also in the leaf axils (where the leaf joins the stem), we select these parts for our cutting material. The whole process is controlled by hormones

new fuchsia plant from leafThis pair of fuchsia leaves (stem cutting) has produced roots, stem, leaves and even flowers. And all this without a propagator. This is the cutting outlined earlier, which was just pushed into soil and grown with the lettuce.

It has taken rather a long time (about 8 weeks) but there is definitely a new plant here. The other cutting has survived as well.

2 June 2010

Lawn Update

Last week's spiking has had some effect. But things are progressing very slowly.

And it's patchy. Some parts are normal; others still rock hard. This is no use for growing. We want all one or all the other. Only then shall we know where we stand.

Decided to fork lawn all over, in rows 10 cm (4 inches) apart, to a depth of 15 cm (6 inches). I then got the hosepipe and filled up the holes a couple of times with water, then applied an inch of water with the sprinkler.

It's much better now. Funny, but I'm sure I could see the lawn growing as I performed this task. Shows how much grass appreciates water and air. This job is rather boring. But in a strange sort of way, I rather enjoy it.

At least we have some defence against a drought and hosepipe ban, now.

Potted Tomato Plants

potted tomato plantTomato plants have been potted out, over 10 days ago, into 30 cm (12 inch) pots of multi-purpose compost to which vermiculite has been added to increase porosity.

They have hardly made progress since purchase, mainly because it has been too cold. The suspected root rot has not materialised. But it takes plants quite some time to get over a bad start (they had been neglected).

As you can see, there is not much leaf. And it is apparently dangerous to give feed too early (which would develop the leaves) in case it stops flowering. Problems, problems.

I have not watered them since planting, although there has been considerable rain. I want to keep them dry to develop the roots. These should go searching for feed and water (there is some feed in the multi-purpose compost). I intend to leave them until they are wilting before watering with 'Phostrogen'. Well, maybe till just before wilting, if I can judge that.

In other words, I am treating them just the same as I would a flowering plant, which, of course, is what they are. We still want lots of flowers. The only difference is that we also want juicy fruits. All this is controlled by watering, as we shall no doubt later discover.

Soil-rooted Fuchsia Cuttings

rooted cuttings after 21 days21 days after pinching out the new 'Hawkshead' fuchsia and placing the tips in garden soil (in a bag propagator), this is the result: new fuchsia plants. Fantastic.

These cuttings have been potted up in multi-purpose compost. As soon as they get large enough, I'll pinch out the tips again. This will give flowers in 8 weeks time with this single fuchsia (10 weeks with double).

It looks as if these cuttings are already forming flowers. These need removing to release energy for leaf and stem growth. There is not enough of it, as yet, to adequately support flowering.

Note that the roots have formed on the stem, not at the node (the place where the leaves are attached). I wonder what would happen if I allowed the internode (the space between the leaf nodes) to become longer before taking the cutting, thus allowing more space for roots to form. Would the seedling grow much quicker? Interesting.

JAWS XVI

holed in basil leafFound this attached to the basil plant, yesterday. I don't know why I always remove things before I have time to photograph them. Must be something to do with unwillingness (Oh, the shame!) to accept failure. It wilted pretty quickly - much quicker than expected.

Must have brought something in with new fuchsias. Trouble is, I don't know what. I am not an expert on jaw (mandible) marks, but these are definitely small, probably a woodlouse or earwig. I don't think it can be slugs; nor caterpillars. Have had a good look round but found nothing. Another mystery.

It is a good idea to keep new purchases in quarantine for a week or two, just in case they are harbouring pests or disease. I went against this advice.

There is also a black sooty smut on the underside of the leaves. Where will it end?

Sprayed basil with 'Rose Clear 3', which is a systemic (travels within the plant) insecticide and fungicide.

This basil is a real problem. Sometimes it is best to admit that one does not have the right conditions (or ability) to grow certain plants, and admit defeat. Think I will keep it just a while longer.

1 June 2010

Fast Grown Stock

fast-grown fuchsia on left, compared with hard-grown on rightBeen to the nursery again and bought another seven fuchsias. Yes, I know. But I couldn't resist. They said they were addictive. I am starting to believe them; I didn't before.

Look how lanky it is compared with our hard-grown specimen purchased in March, on the right.

Most of the fuchsias were trailers, suitable for baskets and containers. Thought I would pick out the best and produce some more plants for next year.