For some plants, “regular” pruning means nothing more than once a year. With evergreen flowering shrubs such as escallonia, which make wonderful flowering hedges and produce blooms on new growth made during the spring, the timing of the annual trim is crucial. Most varieties will flower all summer and well into the autumn. In mild areas, they may be pruned in spring, but where there is a likelihood of late spring frosts I prefer to sacrifice some of the late flowers and prune in early autumn.

Further Readings:

• How to Grow Trees in a Small Garden
• How to Train and Prune Plants

Rejuvenation requires a lot of heavy pruning and some species adapt better to it than others. I have cut eseallonia that were over 40 years old, leaving knee-high stumps about 6 inches across. Within three years, the shrub had revived as a compact flowering plant. Rhododendron, griselinia. forsythia, and philadelphus can also tolerate being cut well into the old wood, leaving just stumps. Within a few seasons, these plants will make a complete recox cry with lots of new branches growing from low down on the plant. Other plants??including lilac (Syringa spp.), broom (Cytisus spp.), lavender and most of the conifers (other than yew)??are less likely to produce new growths from very old wood and are liable to die if pruned back too heavily.

When rejuvenating a shrub in this way, pax particular attention to timing, as any new shoots will need plenty of time to firm up and become woody before the first hard frost. High-potash liquid fertilizer, applied in late summer, will harden the young growths.

When rejuvenating an old plant by heavy pruning, it is very important to make the large cuts at a downward angle to encourage water to run off. Otherwise disease will enter the plant. A proprietary wound sealant should prevent spores from entering the cut, but keep applying it as necessary (perhaps once every six months) over the next couple of seasons, as it may be years before the wound is fully callused over.

Fruiting vines have a more defined system of pruning. If the operation is mismanaged, there will be no crop that year.

There are three main types of vine cultivated for their grapes the European grape (Vitis vinifera) (6-9), the American grape (V.labrusra) (5-9), and hybrids between these two. The difference between the European and American types is that V.vinifera produces the bunches of grapes close to the base of the new growth, while varieties of V. labrusra and the hybrids tend to fruit further along the growth. Both types are usually grown on a straight main stem, with fruits appearing on side growths produced that year.

The most important period for pruning fruiting vines is during winter dormancy, when an enormous amount of the previous year’s growth is removed. European vines are spur-pruned, which means that all of the previous year’s growths are cut buck to within two buds of the old cane. When the new shoots appear, one is removed, leaving a single stem to grow, (the reason why two buds are left to grow on as shoots is in case one is damaged.) Ideally, fruiting shoots are pencil thick with 6-12-inch gaps between the leaves. American varieties of I. labrusra tend to form their fruiting buds further along the stem and they should be pruned back to about ten buds (cane primed). When priming, any thick canes may be left longer than the ten buds.

Europeans have grown grapes under glass for centuries. The best time to prune them is in mid-winter before the sap starts to rise. Pruning later in the season will cause the vine to “bleed” copious amounts of sap from the wounds, draining its energy. To prune grapes grown under glass but once the cluster of flowers gives way to a tiny bunch of grapes, pinch out the growing tip of each shoot, leaving three leaves beyond the bunch. Shorten subsequent laterals to one leaf. Good air circulation is essential when growing grapes, especially in glasshouses. Where bunches of grapes are tightly packed, remove some of the leaves around them to increase air movement and reduce the risk of disease, for improved quality and size (albeit fewer bunches), restrict each stem to one bunch of grapes.

Further Readings:

• How to Build a Grape Trellis
• How to Choose Fruits in Container Gardens

Many gardeners use a hormone rooting powder or gel to encourage cuttings to root more quickly, especially hard-to-root plants such as camellias and rhododendrons. To prevent a potential spread of disease from one batch of plants to another, avoid dipping cuttings directly into the full container of hormone powder. Instead, use small amounts of hormone at a time, decanting it into a clean dish.

The cutting will need a good root system before it is ready to be potted on. Try not to disturb the roots while they are forming. Wait for small white roots to appear at the base of the container and leave the cutting in the container for at least another seven to ten days to enable them to develop further. Once the root system is established, the cuttings can be separated and potted as individual plants.

Softwood cuttings

1. The best time to remove cuttings is in the morning, before the leaves start to transpire. Choose a soft, new growth, such as a young side shoot, and remove it from the parent plant either with a sharp knife or by pulling away the entire shoot with the fingertips. Make sure the “heel” from the main stem is intact. Place the cutting in a sealed, clear plastic bag and store in a cool, shaded room until ready to plant. Cuttings quickly lose moisture and they will wilt if they are not kept in a moist atmosphere.

2. Prepare the cutting using a sharp knife or a razor blade by trimming it immediately below a leaf joint or node??this is the area with the highest concentration of plant hormones. With most plants, you will end up with a cutting 2-4 inches long. Cut or pull off the lower leaves, taking care not to damage the stem or to leave a stump of leaf stalk. Failure to do this will cause the leaves to rot when you insert the cutting into the compost, killing the cutting before it has time to root. Nip out the growing tip of the cutting if there is a flower bud forming.

3. If you are using hormone rooting powder, dip the cutting in it and shake off any excess.

4 Choose a free-draining compost without nutrients. A homemade mixture of equal parts of peat and coarse horticultural grit will be every bit as successful as a proprietary mixture. Fill a seed tray or shallow flowerpot with compost to within 1 inch of the rim. The compost should be moist, not wet. To check whether it is sufficiently moist, remove a handful from the bag and squeeze it in your hand. If it retains its shape, it is fine. If water drips out as you squeeze, it is too wet. Use a stick to make a hole first, ensuring it isn’t too deep for the cutting. The base of the cutting should rest on the base of the hole without an air pocket and the lowest leaves should be clear of the compost. Insert the cuttings in the compost, spacing them 2 inches apart.

5 Firm the compost by hand and water from overhead using a fine rose (sprinkler!. Cover with the propagator lid or a dear plastic bag secured with string or a rubber band.

Tip for taking heather cuttings

You may wish to try this method if you want to root a considerable number of heathers. It works a treat for me.

Fill a seed tray to within 1 inch of the rim with moist rooting compost. Remove enough short 2-inch lengths of heather, taking them from current growths. Nip out the growing tip of each cutting with your fingernails. There is no need to trim off any leaves. Lay the cuttings horizontally on the surface of the compost and dampen with water through a fine rose (sprinkler).

Cut a sheet of clear, horticultural glass slightly smaller than the dimensions of the top of the seed tray. Place it directly on top of the cuttings, pressing down gently to make sure the cuttings are in contact with the compost. Cover the glass with a sheet of newspaper. After a few days, remove the paper and place the tray of cuttings in subdued light, away from strong sunlight. Within a few weeks you will see, through the sheet of glass, small, thread-like, white roots appearing on the surface of the compost. You can now remove the glass and pot up the individual rooted cuttings in pots of fine compost??this time they are inserted vertically??and water them in. Maintain high humidity by covering them with clear plastic for the first few days. And all at no cost.

Cut the stem immediately above a leaf with a healthy bud, angling the cut down and away from the bud. Make a horizontal cut 1 inch below the leaf. Split the stem cutting lengthwise, leaving it the same length but half the thickness, to make a larger wound from which roots will sprout. Dip the stem in rooting powder or gel and insert it in moist cutting compost. Position the leaf at, or just above, the surface.

Place the pot in a heated propagating case and spray regularly with a fine mist of aired (i.e. room-temperature) rainwater. Where there is no propagating case, cover the pot with a clear plastic bag and place in a warm, shaded position. In the case of camellias, the cutting should be well rooted within three months. Take care when potting it up, as the roots will be brittle at this stage. Camellias hate lime, so use an ericaceous compost for potting.

The same method is successful with mahonia, especially if the cuttings are taken in early autumn. Cut the large, spiny leaf in half to reduce transpiration, but don’t split the stem.

For mother-in-law’s tongue, cut the leaf lengthwise into sections 2-3 inches long. Dust the lower cut edge of each section with hormone rooting powder or gel and insert uptight in a tray of moist cutting compost. Position the tray away from strong sunlight. The cuttings from the base of the leaf will root more quickly than those close to the leaf tip. After a period of up to three months plantlets will form at the base of each section of leaf where the vein is in contact with the compost.

Cape primrose leaves may also be cut lengthwise. With a sharp knife, cur along either side of the main, central vein to give two leaf portions. Discard the central vein. Dust the cut edge of each leaf portion with hormone rooting powder or gel. Insert the cut edge into a tray of cutting compost. Keep the compost moist, but avoid damping the foliage of the streptocarpus as the fine hairs on the leaf’s surface tend to rot easily. Eventually, little plantlets will form all along the base of the leaf. .Again, be patient, because this can take anything from 8-20 weeks depending on the time of year.

Leaves of African violets (Saintpaulia spp.) are propagated without removing the leaf’s stalk. Healthy, fully grown leaves may be rooted at any time of year. Cut the leaf off the parent plant with as long a stem as possible. Fill a container with rooting compost, having added one part grit to every five parts of compost to ensure good drainage. Make a hole in the compost with a stick or pencil just off center. Trim the end of the stalk, making a clean, straight cut. Take care not to bruise the soft stalk.

I don’t use rooting powder for African violets, simply because I have found that they don’t need it. Insert the leafstalk upright, keeping the leaf slightly above the surface of the compost and facing into the pot to leave space for the new plants. Within six weeks, new plants will have formed on the surface. These may be separated and potted on.

Leaf cuttings

1. Select a healthy, unblemished leaf [here, Begonia rex) and remove it from the plant.

2. Remove the stalk from the leaf, then cut through the main veins on the underside of the leaf using a sharp knife.

3. Fill a seed tray with cutting compost. Water lightly with a sprinkler and place the leaf on the moist compost, underside down. To make sure the cut veins are in contact with the compost, peg the leaf down flat using U-shaped pieces of fine wire, or weigh it down with stones. Keep the tray away from direct sunlight.

4. Plantlets will form at the cut veins, but be patient, as in some cases this can take months.

5. When the plantlets are well rooted (here after about three monthsl, they may be lifted and potted up.

Don’t underestimate the importance of pricking out??it has been shown that tomato seedlings pricked out within three days of emergence made plants nearly twice the size of those left together in their first pot lot a week or more.

When choosing a container lot transplanting, avoid using one that is too big. Tiny seedlings usually do best in small pots, cells, or boxed trays until they are strong enough to colonize a larger ball of compost. And, just as importantly perhaps, where are you going to keep all those big pots? As they grow, the seedlings can be potted on into larger containers.

If your seedlings have been growing in a protected environment, such as a greenhouse or propagator, make sure you maintain the same conditions alter pricking out of potting on??so, if they have been kept in a warm place, put them back there. Only when they have reestablished in their new compost can you risk moving them.

Pricking out a young seedling

1. Seedlings are big enough to prick out when you can handle them by their first leaves which have fully unfurled. It is riskier to touch either the stem or central tip.

2. These seedlings are already overcrowded??pricking out should have been done days ago.

3. Make sure the seedlings have been watered thoroughly well before attempting to remove them. This will encourage the compost to stick to the roots and help prevent them getting damaged. Rattle the pot, cell, or tray to loosen the compost, then carefully tease out a rooted seedling, keeping the root intact. Use a pencil to help extricate the thread-sized roots. A pencil or stick is helpful to tease the seedling from its container.

4. DON’T hold plants like this – you’ll bruise the fragile stem.

5 Choose a small pot, cell, or boxed tray. Fill with sieved sterile potting compost. Use a pencil or dibber to make a hole in the compost and transfer the seedling immediately. Firm gently but very firmly. Partly immerse the pot/tray in warm water until the surface appears damp, then immediately drain. Do not water from the top, or wet the compost, before pricking out. Once transplanted, place the seedlings back in the greenhouse, propagator, or sheltered spot in the garden until they have started to grow strongly and need potting on.

Instruction – Potting on

1. It is impossible to tell by looking at the top of the plant if it is ready for potting on. One clue, though, might be if it keeps drying out between waterings. You need to examine the rootball, so knock the plant out of its pot and have a look.

If there are few roots visible, leave the plant to establish for a little longer.

2 If you can see lots of roots, now is the perfect time to pot on.

3 If there is a great mass of congested roots with no compost visible, tease them out under water…

4. …and plant up immediately.

1. Line the base of the planter with a 1 inch layer of drainage material.

2. Take a 1 inch plastic pipe, cut so it’s long enough to reach from the base of the planter to just above the final level of compost, and drill holes in the sides so it’s like a colander. Insert the pipe in the center of the planter.

3. Fill the bottom half of the planter with potting compost with added grit, firming it around the pipe, until it reaches just below the level of the lowest planting hole.

4. Depending on the size of the rootball, push one of the herbs through the planting hole from the outside….

5 ….or (preferably) wrap the foliage in plastic from an old fertilizer sack and thread the herb through the planting hole from the inside out.

6. Build up another layer of compost and repeat the process. Top up the compost until it is just below the top of the plastic pipe.

7. Fill the pipe with gravel.

8. Place the pot in a sunny position and rotate it regularly for even growth

Many molds, mildews, and rusts don’t even start unless the plants are under water stress; thus it is crucial to keep their compost or soil moist, especially when the air is damp or stagnant. Most of these infections need to “germinate” in a wet droplet and most become much less troublesome when the plants are in drier air??so open pruning can help make old congested plants healthier. So compost, like soil, must be kept moist but not waterlogged and fertility should likewise be balanced with sufficient nutrients to promote growth without forcing it and must be of a suitable acid/alkaline range, usually with plenty of humus, and grit, clay and sand to balance.

All plants must have adequate airflow, but nor drafts, especially under cover where carbon dioxide may be used up if insufficient ventilation is provided. Plants also require freedom from competition if they are to do well. It does not matter much whether the other plants are weeds or more of the same kind??each one needs sufficient soil or compost and light to flourish, so any overcrowding should be thinned to prevent the plants becoming weak or spindly.