March in the Garden 

March is a busy maintenance month in the garden. Prepare beds for autumn annual planting. You should work in about 3 to 5cm of compost into the soil. This will ensure that plants have the nutrition they require to get off to a great start. 

Give your soil nutrients so that the plants in your garden have the ability to become strong and healthy. Use a general fertiliser like a 2:3:2 which has a lot of phosphate in it and a good balance of nitrogen and potassium, (also known as potash), and can be used in addition to the compost at the recommended rate. One could also use a fertiliser such as 8:1:5 at this time of year with the compost. 

Sow

Autumn means it’s time to start sowing winter and spring flowering annual seeds. Some of our favourites to sow now are:

Sweet Peas: Their seductive fragrance in the garden or as cut flowers in the home is like no other. The seed is generally available in mixed colours, which are a gorgeous mix of mostly pastel colours, for both dwarf and climbing varieties. The climbing sweet peas will need a sunny spot with supports to climb up – like a trellis, fence or an arch. Sweet peas will be happiest with their roots are in cool, moist soil, so remember to mulch well. The secret to fabulous sweet peas starts with the soil preparation. Dig over a trench of soil, next to the supports, to the depth of a garden fork and add plenty of compost and preferably manure too. (Sweet peas have a large strong root system that develops quite deep, so when planting them you need to prepare the soil much deeper than what you normally would). Use a pencil-like stick to make 3 to 5cm deep holes and drop the soaked seeds in, cover the holes and water well. Keep the area well-watered. 

Tips: Soak the seeds in luke-warm or cool water, (not boiling!), overnight before planting to soften the seed covering which will give much better germination. Sow at about 2 weekly intervals for a longer-lasting show of flowers. To encourage bushy growth, cut off the tips of plants only when they are about 15 to 20cm tall (and not sooner). Don’t forget to feed your plants regularly as they are heavy feeders.

Pansies: Are a winter and spring flowering favourite for the sun. Their colourful blooms are available in a wide range of single and bi-colours. They can be used as massed flower borders, in pots and window boxes or as fillers between spring-flowering bulbs and roses. Pansies typically have large and medium-sized blooms while their smaller flowering “cousins” violas have medium-sized to dainty little flowers. The larger flowers are showy and suited close to entertainment areas or pathways. The medium-sized pansies and violas often have more flowers and are a hit when used as a massed display in the garden. 

Tip: Pansy and viola flowers can be used as a garnish or as edible flowers in salads.

Primulas: Fairy primroses, (Primula malacoides), are still a favourite for winter and spring flowering colour in the shade or semi-shade. They have dainty, tiered flowers and are available in white, lavender, rose, pink and a darker pink/purple. White primulas will brighten up shady patches the most and show up well in the evening. A plus is that fairy primroses are self-seeding.

Sow, sow & sow: Calendulas, (Calendula officinalis) have edible “petals” that look super sprinkled on winter soups. Iceland poppies are available in stunning mixed colours – choose cultivars with strong stems for windy gardens. A few others include; Livingstone daisy, (indigenous Mesembranthemums), godetia, (Clarkia amoena – also known as poor man’s orchid), for the sun. (Tip: Before buying seed always check the sowing time on the back of the seed packets for your region’s best sowing months, sowing depths and final spacing). 

Plant

Garlic: There is nothing better than cooking with fresh produce from the garden and Garlic bulbs are available in garden centres at this time of year. Simply prepare a sunny bed with compost, and either bonemeal or superphosphate at the recommended rate. Plant the individual cloves about 10 to 15cm apart and about 3 to 5 cm deep, making sure that the pointy side faces upwards. If your soil has poor drainage then plant them in raised beds or even containers. Garlic wards off many pests with its pungent smell and is, therefore, a great addition to any veggie garden. (Garlic is not well suited to very humid, hot areas of the country).

Pelargoniums: Bush geraniums, (Pelargonium x hortorum), and ivy or cascading geraniums, (Pelargonium peltatum), are still some of the “jewels in the crown” of our indigenous plants even though they have been heavily hybridized. Geraniums are one of the most rewarding garden plants and are ideally planted in containers on your patio in a sunny to semi-shade position. Geraniums love to be planted in a well-drained soils that should be moist but not wet. Give them a weak but regular, (preferably weekly), liquid feeding. 

Spray

Amaryllis caterpillar/worm: Keep a lookout for wilting leaves or flowers on any of the lilies like arum lilies, amaryllis, agapanthus and clivias. Inspect the plants by pulling the leaves open to reveal the “middle” of the plant above the bulb – the Amaryllis worm is normally easily spotted in this area if they are the culprit. They may be between the epidermal layers of the leaves or openly chewing close to the base of the leaves and flower stalks. The base of the leaves will also become slimy, smelly and pulpy. Ask your local garden centre for a recommended spray.

White grubs: The adult chafer beetles sometimes lay their eggs in the lawn and the grubs that hatch feed on mostly decaying organic matter but also the lawn roots and underground lawn stems. The lawn or leaf blades start to wither and die in patches. If you want to confirm your suspicions, you should be able to easily pull up pieces of lawn and see the large, fat white grubs curled up in a c-shape. Ask for advice at your garden centre and treat as recommended. 

Pick

Roses: Roses are prized cut flowers. Most hybrid tea roses produce individual blooms on strong stems and are great for picking. Fragrant blooms add that extra sensory dimension.

Inca lilies, (or peruvian lily): Also known by their botanical name of Alstroemeria, (Alstoemeria indica), inca lily blooms are best harvested by firmly holding the flowering stem close to the base and twisting the stem as you pull it upwards. This will help the detach the flower from the underground stem and promote further growth and flowering.

Bedding besties

Snapdragons: Most snapdragons, (Antirrhinum majus), are either slightly or moderately scented which is great if you like to cut flowers from the garden or one can place them close to the home. Snapdragons love the sun and varieties range from tall, (over 60cm tall which may require staking), or as short as 15cm for the dwarf ones, and come in a range of beautiful colours and colour mixes. They are long-lasting in the garden and will grow through our mild winters and flower into spring.

Blooming babes

Calibrachoa, Million Bells or trailing petunia is a trendy treasure that has yet to be discovered by many gardeners, calibrachoa. This is a trailing plant, that gets covered in hundreds of small bell-shaped flowers that are quite dazzling. They are the first choices for planting in containers and hanging baskets for gardeners that have had them before. Although sun-loving, in very hot areas they will do better in semi-shade. They are available right now in shades of violet, blue, pink, red, magenta, yellow, bronze and white as instant colour plants in pots and hanging baskets. They can be pinched back from time to time to encourage bushy growth and more flowers. 

Tip: Feed calibrachoa with a liquid fertilizer regularly to encourage healthy growth and flowering.

Rose care

Roses are simply spectacular in autumn! To ensure quality blooms into the winter, continue with regular preventative spraying for black spot. As the days get shorter, the roses start to go dormant and withdraw food from their leaves. To compensate for this and to provide enough food for new growth and flowers, fertilize with rose food – your local GCA garden centre will advise you on the best option. Regular watering is very important if there is insufficient rainfall.

Water-wise 

One of the best ways to save water in the garden is to hydro-zone the plants in your garden. Hydro-zoning means that you position plants in the garden, or in containers, according to their water requirements so that we do not use any more water in any hydro-zone than the plants positioned there require. We, therefore, group all plants that like the most water together and these are commonly known by your garden centre staff as 3 drop plants, those that require a medium amount of water 2 drop plants and the water-wise, low water requirement plants as 1 drop plants. Where possible keep the 3 drop zone to a minimum – perhaps around a swimming pool or entertainment area, and in the same way make the 1 drop zone the largest area of your planted garden, (since paved areas effectively constitute a 0 drop zone). There is no better time to start than today – have fun and save our precious water.

Inland gardening

Compost: Compost is the equivalent organic gold to the garden! With all the autumn leaves combined with the vegetable kitchen waste, it is a great time to start your compost heap now. Lightweight and easy to use compost bins are readily available at your local GCA Garden Centre, to fit even the smallest of gardens. Ask for compost accelerator at your garden centre and add this to the various layers of compost being added. 

Tips: Avoid adding any plants that are diseased or pest-ridden, as well as weeds with seeds or seed heads on them. Lawn clippings should be thinly layered between other layers of waste otherwise they will rot and form a slimy mess in the bin. 

Lift and divide

It’s time to lift and divide summer flowering perennials. Here are some examples of the most common ones: agapanthus also known as african lily or nile lily, (Agapanthus spp.), wild iris, (Dietes bicolor and Dietes grandiflora), penstemon, campanulas and asters. Most perennials start to decline in vigour from being too close to one another after several seasons of pushing fresh outward growth and therefore require division, (normally only once in 3 to 5 years), to “refresh their vigour or growth. Simply cut the foliage back by about two thirds, lift them carefully form the soil and then divide them by hand or by using two garden forks, (back to back). Split up into fresh, healthy-looking clumps and plant them in well-prepared soil that has compost and either bonemeal or superphosphate at the recommended rate, so that good root growth is initiated. Water well. 

Coastal gardening

Cut back all summer flowering perennials that are looking tired. Pay attention to salvias (also known as sage), daisies, lavender and fuchsias.

Frangipani, (Plumeria rubra), grows well in full sun in the tropical and subtropical areas of the country. If you are looking for that tropical island feel in your garden, this small tree will certainly give “the look”. They withstand drought and bloom profusely from late spring through summer and into autumn. There is a wide range of beautifully coloured flowers that are richly fragrant. They are easy to grow and with little attention, flourish in almost all soil types.

Hot tip: It may still be too hot to plant spring-flowering bulbs. Good advice would be to buy them while they are available and store them in the vegetable compartment of the refrigerator and plant out when the weather cools down in a month or two. 

Days of interest:

03 March – World Wildlife Day

21 March – Human Rights Day

21 March – World Water Day

21 March – International Day of Forestry