When to plant is one of those questions we get asked a lot. So we’ve just put together a few tips to give you our best advice but really its not too difficult. Now (March) is a great time for planting most things including trees, shrubs and perennials. But it is still too early for sowing some vegetables outside and your tender summer bedding. More detail below:
In general, you can plant trees and shrubs all year round as long as the soil isn’t frozen, covered with snow or waterlogged. Bear in mind though that if we have a hot summer and it is really dry you will need to keep the plants well watered. This applies to container grown plants, bare-rooted plants should be planted in the autumn when the soil is still warm.
Planting Trees
The best time to plant trees is late autumn to early spring (October to March) when they are in a dormant state. Most apple trees are planted October to December.
Prepare the soil a couple of weeks before planting by digging in plenty of organic material. To plant simply dig a hole large enough to take the roots, generally twice the size of the pot, place the tree in the hole and cover the roots with soil up to the surrounding ground level. Trees should be planted in a square hole to encourage even rooting. The tree should be planted to the same depth as it was in the pot and not any deeper – the biggest cause of tree death is planting too deeply. Having planted the tree, firm down the soil using your boots to ensure the soil is in good contact with the roots and water well to wash the soil in around its roots.
(Note – when planting fruit trees the graft union should be at least 3-4 inches above soil level).
If necessary the tree should be staked, with the stake being driven into the soil at a 45 degree angle, being careful not to go through the root ball. Tie the trunk to the stake using plastic tree ties available from the garden centre. Do not use wire or string as this will cut into the tree trunk with time and damage it. You will need to check the tie in the first couple of years to ensure that they don’t become too tight.
Planting Shrubs
Plant evergreens (laurels, photinias, elaeagnus etc) in early to mid-autumn or mid to late spring, and deciduous shrubs (wiegela, spirea, potentillas etc) between mid-autumn and early spring when soil and weather conditions are favourable. Good soil preparation is important and it is a good idea to dig in good organic matter before you plant to give them a good start. Dig a square hole about twice the size of the pot that the plant is in and loosely fork over the bottom of the hole. Tease out the roots so they are encouraged to grow into the surrounding soil and plant to the same level as they are in the pot and then back fill the hole with soil and firm in. Some shrubs should be planted slightly deeper such as roses and clematis, roses to cover the union of the graft and clematis to discourage wilt but on the whole most shrubs shouldn’t be planted too deeply. Rhododendrons for example always do better if not planted too deeply, as do phormiums, if in doubt check the label. Water in well.
Planting Perennials
Generally, perennials can be planted during autumn or spring, although containerised plants can go in at any time provided the ground is not frozen or waterlogged. Make sure that the root balls are thoroughly soaked before planting, if really dry soak in a bucket for a few minutes. Dig the planting hole of a shape and size to allow the roots to spread comfortably, and at a depth to the level of the crown – the point where the stems and roots join. Firm the plant in and water thoroughly if the soil is dry.
Planting Annuals
Annuals can be planted mid-spring to early summer, depending on the location and the type of plant. Begin with the hardier ones, such as sweet peas and pansies, and finish with the more tender types such as pelargoniums and fuchsias when the danger of frost has subsided. Before planting, water the containers and allow the plants to absorb the moisture before moving them. During dry periods, puddle them in – fill the planting hole with water and allow it to soak in, then set the plant in place and fill the hole with soil.
Planting Bulbs
Spring flowering bulbs such as daffodils and crocus should be planted in the autumn preferably by the end of September. Tulips are best planted in November but can be left to December. As a general rule plant the bulb at a depth that is 3 times the size of the bulb itself ( if a bulb is 1 inch in size then there should be 3 inches from the surface to the top of the bulb). Plant in groups rather than singly. Dig a hole to the required planting depth and then space them at least twice the bulb’s own height and width apart. Carefully replace the soil and gently firm with the back of a rake.
Planting and Sowing vegetables
Growing vegetables from seed can be quite challenging, but basically the thing to remember is not to sow them too early, not too deeply and not too thickly. Sowing also depends on whether you sow indoors or outdoors directly in the soil. Decide on what you want to grow and have a good look at the seed packets for detailed growing information. You also may not want to grow from seed but buy plants from the garden centre if you are short of time and grow them on. Consider growing heritage varieties of veg such as purple peas (Lancashire Lad) or white carrots (White Belgium)
Sowing seed outdoors – Prepare the seed bed in early spring, wait until the soil dries out and doesn’t stick to your boots. Dig over the area you want to plant into (in some cases you will have done this already in the winter) and break down the clods of soil with the back of a fork. Rake level, removing large stones, aiming for the soil to have a consistency of coarse breadcrumbs.
Mark out the row with a taut piece of string and with the edge of a hoe draw out a drill to the depth recommended for the vegetable to be sown. Water the row before sowing, once sown cover the seed gently with soil with back of a rake.
Sowing seed indoors – Choose plastic rather than wooden containers, using trays, small pots or cellular trays and use a seed or multi-purpose compost. Firm the compost in place and water it. Sow according to the instructions on the packet. Do not cover very fine seed with compost. Other seeds should be covered with compost or vermiculite to a depth which is twice the diameter of the seed. Most seeds require a fairly warm temperature to germinate (about 70 degrees F). If you haven’t got access to a greenhouse most seed can germinate on the windowsill of a central heated room. Keep well watered with a fine sprayer ensuring the compost doesn’t dry out.
As soon as the first set of true leaves have opened the seedlings should be pricked out into small pots or cellular trays. Once they get to this stage high temperatures are not required and 50-55 degrees are OK. When the seedlings have recovered from the pricking out move, they must be hardened off to prepare them for life outside. Move to a cold frame and then open on dry frost free days. Later keep them open day and night for 7 days before planting out. Windowsill plantings should be moved into an unheated room before being stood out for a few days prior to planting outside in the garden.
January
• Sow Bulb Onions seeds under glass
February
• Sow early Carrot seeds in a cold frame
• Sow Bulb Onions and Lettuces under glass
• Sow Beetroot, Spinach and Carrots in the soil, will need protection
March
• Continue to sow Early Peas and Broad Beans in mild areas
• Sow Lettuces, Radishes and Spring Onions in the soil
• Sow Summer Cabbages, Leeks and Brussels Sprouts in a seed bed
• Sow Tomato seeds in trays or pots and keep at 18°C (65°F)
• Sow Beetroots, Carrots and Turnips in the soil
• In the south, plant Early Potatoes and Onion Sets at the end of the month providing the soil is not excessively wet
April
• Continue to sow Lettuces, Radishes and Spring Onions in the soil
• Sow Cucumbers, Marrows, Pumpkins and Squashes under glass
• Sow Winter Cabbages and Late Summer Cauliflowers in a seed bed
• Continue to plant Onion Sets
• Plant out Onions grown from seed under glass into the soil
• Plant out Asparagus crowns (will take 2 years for harvest)
• Sow leaf beet and chard outside
• In the north, plant Early Potatoes providing the soil is not excessively wet
• Plant Main Crop Potatoes
• Plant Onion Sets and Potatoes in the middle of the month unless the soil is excessively wet
• Plant Tomatoes in the greenhouse or in cold frame
May
• Continue to sow Lettuces, Radishes and Spring Onions in the soil
• In the north, sow Runner Beans under glass
• Sow French Beans, Runner Beans and Long Rooted Beetroot towards the end of the month when the frost risk has subsided
• Plant out Late Summer Cauliflowers
• In the north, plant out Brussels Sprouts
• Plant out Cucumbers, Marrows, Pumpkins and Squashes towards the end of the month
June
• Continue to sow French Beans, Peas and salad crops in the soil
• Continue to plant out Cucumbers, Marrows, Pumpkins and Squashes
• Plant out Brussels Sprouts and Winter Cabbages
• Plant out Tomatoes
• Plant out Leeks
July
• Continue to sow salad crops in the soil
• Complete planting Brussels Sprouts, Leeks and Winter Cabbages
August
• Sow early Spring Cabbages
September
• Plant out Spring Cabbages towards the end of the month
November Sow autumn broad beans such as Aquadulce to provide beans for June
Grey Gardeners 