Watering and Weeding
Home Vegetable Gardening
Course 1 · Chapter 6 · Watering and Weeding: How Much, When, Mulching and Weed Types
Chapter 5 ended with plants watered in. From here, two jobs fill most of the gardener's routine: keeping water supplied and keeping weeds in check. Both are easier with a few good habits than with constant effort.
How Much and When to Water
Most vegetables need roughly the equivalent of 2.5 cm (an inch) of water a week in the growing season, from rain and watering together (check). In practice, check the soil rather than the calendar: push a finger in to about 5 cm. If it is dry there, water.
- Water deeply and less often. A thorough soak every few days pushes roots down; a daily sprinkle keeps them near the surface and makes plants fragile in dry spells.
- Water in the morning if you can. Less is lost to evaporation, and leaves dry before night, which reduces slugs and disease. Evening is the second choice.
- Water at the base, not over the leaves, aiming at the soil where the roots are.
- Containers dry out fastest. In warm weather they may need water every day.
- Collect rainwater in a water butt where you can. Plants like it, and it is free.
| Crop stage | Water need |
|---|---|
| Seedlings and new transplants | Frequent, gentle; roots are small |
| Leafy crops (lettuce, spinach) | Steady; dry spells make them bolt (run to seed) and turn bitter |
| Fruiting crops (tomatoes, courgettes) | Steady while flowers and fruit form; uneven watering can split fruit (check) |
| Root crops (carrots, beetroot) | Even moisture; big swings cause splitting |
| Established deep-rooted crops | Less often but deeply |
Mulching
A mulch is a layer of material spread over the soil surface. Chapter 3 introduced it as a way to feed soil; it also saves water and suppresses weeds. Spread 5 to 7 cm of compost, well-rotted manure, leaf mould or straw on damp, weeded soil, leaving a gap around plant stems so they do not rot.
Bare soil
Dries out quickly, bakes hard, and is quickly colonised by weed seeds.
Mulched soil
Stays damp longer, stays cooler in summer, blocks light from weed seeds, and feeds worms as the mulch breaks down.
Mulch on soil that is already dry just seals the dryness in, so water well first. Fresh grass clippings work in thin layers but turn slimy if piled thick (check).
Weed Types
A weed is simply a plant growing where you do not want it. Knowing how a weed spreads tells you how to deal with it.
| Type | Examples | How to deal with it |
|---|---|---|
| Annual weeds | chickweed, groundsel, shepherd's purse | Hoe or pull before they set seed; one plant can drop thousands of seeds |
| Perennial, taproot | dandelion, dock | Dig out the whole root; any piece left can regrow |
| Perennial, creeping roots | bindweed, couch grass, ground elder | Fork out carefully, removing all root pieces; persistence over months, or cover with a light-proof layer for a year or more (check) |
| Perennial, runners | creeping buttercup | Lift runners and roots; mulch to starve |
Not Yet Verified, and Sources
- Source. Written from general knowledge of gardening; no specific source was read. Nothing is quoted from a text.
- Marked (check). The weekly water figure, effects of uneven watering on fruit, grass-clipping mulch, covering to kill creeping perennials, composting weeds, and weeds as soil indicators. Verify against local gardening advice.
Exercises
A warm week has passed with no rain. You have a raised bed of lettuce, a row of carrots and two tomato plants in pots. Write a watering plan for the week, saying how you would check each, when you would water and how much.
Describe how you would mulch a 2 m by 1 m bed of established vegetables: which material, how deep, when, and what you would do first and avoid doing.
You find chickweed, a dandelion and bindweed in the same bed. Explain which type each is and what method you would use to remove each one.
Quick Reference
- Test: finger 5 cm into the soil before watering
- Method: deep, less often, at the base, in the morning
- Mulch: 5-7 cm on damp soil, clear of stems
- Annual weeds: hoe before seeding
- Taproot weeds: dig out the whole root
- Creeping weeds: fork out all pieces, persist, or smother